Telegram iComsium Current root: /home/mukeshgusaiana/thelostera/public_html/wp-content/themes/generatepress
Current path: /home/mukeshgusaiana/thelostera/public_html/wp-content/themes/generatepress

Dosya Düzenle: class-wpdb.php

<?php
/**
 * WordPress database access abstraction class.
 *
 * Original code from {@link http://php.justinvincent.com Justin Vincent (justin@visunet.ie)}
 *
 * @package WordPress
 * @subpackage Database
 * @since 0.71
 */

/**
 * @since 0.71
 */
define( 'EZSQL_VERSION', 'WP1.25' );

/**
 * @since 0.71
 */
define( 'OBJECT', 'OBJECT' );
// phpcs:ignore Generic.NamingConventions.UpperCaseConstantName.ConstantNotUpperCase
define( 'object', 'OBJECT' ); // Back compat.

/**
 * @since 2.5.0
 */
define( 'OBJECT_K', 'OBJECT_K' );

/**
 * @since 0.71
 */
define( 'ARRAY_A', 'ARRAY_A' );

/**
 * @since 0.71
 */
define( 'ARRAY_N', 'ARRAY_N' );

/**
 * WordPress database access abstraction class.
 *
 * This class is used to interact with a database without needing to use raw SQL statements.
 * By default, WordPress uses this class to instantiate the global $wpdb object, providing
 * access to the WordPress database.
 *
 * It is possible to replace the global instance with your own by setting the $wpdb global variable
 * in wp-content/db.php file to your class. The wpdb class will still be included, so you can
 * extend it or simply use your own.
 *
 * @link https://developer.wordpress.org/reference/classes/wpdb/
 *
 * @since 0.71
 */
#[AllowDynamicProperties]
class wpdb {

/**
	 * Whether to show SQL/DB errors.
	 *
	 * Default is to show errors if both WP_DEBUG and WP_DEBUG_DISPLAY evaluate to true.
	 *
	 * @since 0.71
	 *
	 * @var bool
	 */
	public $show_errors = false;

/**
	 * Whether to suppress errors during the DB bootstrapping. Default false.
	 *
	 * @since 2.5.0
	 *
	 * @var bool
	 */
	public $suppress_errors = false;

/**
	 * The error encountered during the last query.
	 *
	 * @since 2.5.0
	 *
	 * @var string
	 */
	public $last_error = '';

/**
	 * The number of queries made.
	 *
	 * @since 1.2.0
	 *
	 * @var int
	 */
	public $num_queries = 0;

/**
	 * Count of rows returned by the last query.
	 *
	 * @since 0.71
	 *
	 * @var int
	 */
	public $num_rows = 0;

/**
	 * Count of rows affected by the last query.
	 *
	 * @since 0.71
	 *
	 * @var int
	 */
	public $rows_affected = 0;

/**
	 * The ID generated for an AUTO_INCREMENT column by the last query (usually INSERT).
	 *
	 * @since 0.71
	 *
	 * @var int
	 */
	public $insert_id = 0;

/**
	 * The last query made.
	 *
	 * @since 0.71
	 *
	 * @var string
	 */
	public $last_query;

/**
	 * Results of the last query.
	 *
	 * @since 0.71
	 *
	 * @var stdClass[]|null
	 */
	public $last_result;

/**
	 * Database query result.
	 *
	 * Possible values:
	 *
	 * - `mysqli_result` instance for successful SELECT, SHOW, DESCRIBE, or EXPLAIN queries
	 * - `true` for other query types that were successful
	 * - `null` if a query is yet to be made or if the result has since been flushed
	 * - `false` if the query returned an error
	 *
	 * @since 0.71
	 *
	 * @var mysqli_result|bool|null
	 */
	protected $result;

/**
	 * Cached column info, for confidence checking data before inserting.
	 *
	 * @since 4.2.0
	 *
	 * @var array
	 */
	protected $col_meta = array();

/**
	 * Calculated character sets keyed by table name.
	 *
	 * @since 4.2.0
	 *
	 * @var string[]
	 */
	protected $table_charset = array();

/**
	 * Whether text fields in the current query need to be confidence checked.
	 *
	 * @since 4.2.0
	 *
	 * @var bool
	 */
	protected $check_current_query = true;

/**
	 * Flag to ensure we don't run into recursion problems when checking the collation.
	 *
	 * @since 4.2.0
	 *
	 * @see wpdb::check_safe_collation()
	 * @var bool
	 */
	private $checking_collation = false;

/**
	 * Saved info on the table column.
	 *
	 * @since 0.71
	 *
	 * @var array
	 */
	protected $col_info;

/**
	 * Log of queries that were executed, for debugging purposes.
	 *
	 * @since 1.5.0
	 * @since 2.5.0 The third element in each query log was added to record the calling functions.
	 * @since 5.1.0 The fourth element in each query log was added to record the start time.
	 * @since 5.3.0 The fifth element in each query log was added to record custom data.
	 *
	 * @var array[] {
	 *     Array of arrays containing information about queries that were executed.
	 *
	 *     @type array ...$0 {
	 *         Data for each query.
	 *
	 *         @type string $0 The query's SQL.
	 *         @type float  $1 Total time spent on the query, in seconds.
	 *         @type string $2 Comma-separated list of the calling functions.
	 *         @type float  $3 Unix timestamp of the time at the start of the query.
	 *         @type array  $4 Custom query data.
	 *     }
	 * }
	 */
	public $queries;

/**
	 * The number of times to retry reconnecting before dying. Default 5.
	 *
	 * @since 3.9.0
	 *
	 * @see wpdb::check_connection()
	 * @var int
	 */
	protected $reconnect_retries = 5;

/**
	 * WordPress table prefix.
	 *
	 * You can set this to have multiple WordPress installations in a single database.
	 *
	 * @since 2.5.0
	 *
	 * @var string
	 */
	public $prefix = '';

/**
	 * WordPress base table prefix.
	 *
	 * @since 3.0.0
	 *
	 * @var string
	 */
	public $base_prefix;

/**
	 * Whether the database queries are ready to start executing.
	 *
	 * @since 2.3.2
	 *
	 * @var bool
	 */
	public $ready = false;

/**
	 * Blog ID.
	 *
	 * @since 3.0.0
	 *
	 * @var int
	 */
	public $blogid = 0;

/**
	 * Site ID.
	 *
	 * @since 3.0.0
	 *
	 * @var int
	 */
	public $siteid = 0;

/**
	 * List of WordPress per-site tables.
	 *
	 * @since 2.5.0
	 *
	 * @see wpdb::tables()
	 * @var string[]
	 */
	public $tables = array(
		'posts',
		'comments',
		'links',
		'options',
		'postmeta',
		'terms',
		'term_taxonomy',
		'term_relationships',
		'termmeta',
		'commentmeta',
	);

/**
	 * List of deprecated WordPress tables.
	 *
	 * 'categories', 'post2cat', and 'link2cat' were deprecated in 2.3.0, db version 5539.
	 *
	 * @since 2.9.0
	 *
	 * @see wpdb::tables()
	 * @var string[]
	 */
	public $old_tables = array( 'categories', 'post2cat', 'link2cat' );

/**
	 * List of WordPress global tables.
	 *
	 * @since 3.0.0
	 *
	 * @see wpdb::tables()
	 * @var string[]
	 */
	public $global_tables = array( 'users', 'usermeta' );

/**
	 * List of Multisite global tables.
	 *
	 * @since 3.0.0
	 *
	 * @see wpdb::tables()
	 * @var string[]
	 */
	public $ms_global_tables = array(
		'blogs',
		'blogmeta',
		'signups',
		'site',
		'sitemeta',
		'registration_log',
	);

/**
	 * List of deprecated WordPress Multisite global tables.
	 *
	 * @since 6.1.0
	 *
	 * @see wpdb::tables()
	 * @var string[]
	 */
	public $old_ms_global_tables = array( 'sitecategories' );

/**
	 * WordPress Comments table.
	 *
	 * @since 1.5.0
	 *
	 * @var string
	 */
	public $comments;

/**
	 * WordPress Comment Metadata table.
	 *
	 * @since 2.9.0
	 *
	 * @var string
	 */
	public $commentmeta;

/**
	 * WordPress Links table.
	 *
	 * @since 1.5.0
	 *
	 * @var string
	 */
	public $links;

/**
	 * WordPress Options table.
	 *
	 * @since 1.5.0
	 *
	 * @var string
	 */
	public $options;

/**
	 * WordPress Post Metadata table.
	 *
	 * @since 1.5.0
	 *
	 * @var string
	 */
	public $postmeta;

/**
	 * WordPress Posts table.
	 *
	 * @since 1.5.0
	 *
	 * @var string
	 */
	public $posts;

/**
	 * WordPress Terms table.
	 *
	 * @since 2.3.0
	 *
	 * @var string
	 */
	public $terms;

/**
	 * WordPress Term Relationships table.
	 *
	 * @since 2.3.0
	 *
	 * @var string
	 */
	public $term_relationships;

/**
	 * WordPress Term Taxonomy table.
	 *
	 * @since 2.3.0
	 *
	 * @var string
	 */
	public $term_taxonomy;

/**
	 * WordPress Term Meta table.
	 *
	 * @since 4.4.0
	 *
	 * @var string
	 */
	public $termmeta;

//
	// Global and Multisite tables
	//

/**
	 * WordPress User Metadata table.
	 *
	 * @since 2.3.0
	 *
	 * @var string
	 */
	public $usermeta;

/**
	 * WordPress Users table.
	 *
	 * @since 1.5.0
	 *
	 * @var string
	 */
	public $users;

/**
	 * Multisite Blogs table.
	 *
	 * @since 3.0.0
	 *
	 * @var string|null
	 */
	public $blogs;

/**
	 * Multisite Blog Metadata table.
	 *
	 * @since 5.1.0
	 *
	 * @var string|null
	 */
	public $blogmeta;

/**
	 * Multisite Registration Log table.
	 *
	 * @since 3.0.0
	 *
	 * @var string|null
	 */
	public $registration_log;

/**
	 * Multisite Signups table.
	 *
	 * @since 3.0.0
	 *
	 * @var string|null
	 */
	public $signups;

/**
	 * Multisite Sites table.
	 *
	 * @since 3.0.0
	 *
	 * @var string|null
	 */
	public $site;

/**
	 * Multisite Sitewide Terms table.
	 *
	 * @since 3.0.0
	 *
	 * @var string|null
	 */
	public $sitecategories;

/**
	 * Multisite Site Metadata table.
	 *
	 * @since 3.0.0
	 *
	 * @var string|null
	 */
	public $sitemeta;

/**
	 * Format specifiers for DB columns.
	 *
	 * Columns not listed here default to %s. Initialized during WP load.
	 * Keys are column names, values are format types: 'ID' => '%d'.
	 *
	 * @since 2.8.0
	 *
	 * @see wpdb::prepare()
	 * @see wpdb::insert()
	 * @see wpdb::update()
	 * @see wpdb::delete()
	 * @see wp_set_wpdb_vars()
	 * @var array
	 */
	public $field_types = array();

/**
	 * Database table columns charset.
	 *
	 * @since 2.2.0
	 *
	 * @var string
	 */
	public $charset;

/**
	 * Database table columns collate.
	 *
	 * @since 2.2.0
	 *
	 * @var string
	 */
	public $collate;

/**
	 * Database Username.
	 *
	 * @since 2.9.0
	 *
	 * @var string
	 */
	protected $dbuser;

/**
	 * Database Password.
	 *
	 * @since 3.1.0
	 *
	 * @var string
	 */
	protected $dbpassword;

/**
	 * Database Name.
	 *
	 * @since 3.1.0
	 *
	 * @var string
	 */
	protected $dbname;

/**
	 * Database Host.
	 *
	 * @since 3.1.0
	 *
	 * @var string
	 */
	protected $dbhost;

/**
	 * Database handle.
	 *
	 * Possible values:
	 *
	 * - `mysqli` instance during normal operation
	 * - `null` if the connection is yet to be made or has been closed
	 * - `false` if the connection has failed
	 *
	 * @since 0.71
	 *
	 * @var mysqli|false|null
	 */
	protected $dbh;

/**
	 * A textual description of the last query/get_row/get_var call.
	 *
	 * @since 3.0.0
	 *
	 * @var string
	 */
	public $func_call;

/**
	 * Whether MySQL is used as the database engine.
	 *
	 * Set in wpdb::db_connect() to true, by default. This is used when checking
	 * against the required MySQL version for WordPress. Normally, a replacement
	 * database drop-in (db.php) will skip these checks, but setting this to true
	 * will force the checks to occur.
	 *
	 * @since 3.3.0
	 *
	 * @var bool
	 */
	public $is_mysql = null;

/**
	 * A list of incompatible SQL modes.
	 *
	 * @since 3.9.0
	 *
	 * @var string[]
	 */
	protected $incompatible_modes = array(
		'NO_ZERO_DATE',
		'ONLY_FULL_GROUP_BY',
		'STRICT_TRANS_TABLES',
		'STRICT_ALL_TABLES',
		'TRADITIONAL',
		'ANSI',
	);

/**
	 * Backward compatibility, where wpdb::prepare() has not quoted formatted/argnum placeholders.
	 *
	 * This is often used for table/field names (before %i was supported), and sometimes string formatting, e.g.
	 *
	 *     $wpdb->prepare( 'WHERE `%1$s` = "%2$s something %3$s" OR %1$s = "%4$-10s"', 'field_1', 'a', 'b', 'c' );
	 *
	 * But it's risky, e.g. forgetting to add quotes, resulting in SQL Injection vulnerabilities:
	 *
	 *     $wpdb->prepare( 'WHERE (id = %1s) OR (id = %2$s)', $_GET['id'], $_GET['id'] ); // ?id=id
	 *
	 * This feature is preserved while plugin authors update their code to use safer approaches:
	 *
	 *     $_GET['key'] = 'a`b';
	 *
	 *     $wpdb->prepare( 'WHERE %1s = %s',        $_GET['key'], $_GET['value'] ); // WHERE a`b = 'value'
	 *     $wpdb->prepare( 'WHERE `%1$s` = "%2$s"', $_GET['key'], $_GET['value'] ); // WHERE `a`b` = "value"
	 *
	 *     $wpdb->prepare( 'WHERE %i = %s',         $_GET['key'], $_GET['value'] ); // WHERE `a``b` = 'value'
	 *
	 * While changing to false will be fine for queries not using formatted/argnum placeholders,
	 * any remaining cases are most likely going to result in SQL errors (good, in a way):
	 *
	 *     $wpdb->prepare( 'WHERE %1$s = "%2$-10s"', 'my_field', 'my_value' );
	 *     true  = WHERE my_field = "my_value  "
	 *     false = WHERE 'my_field' = "'my_value  '"
	 *
	 * But there may be some queries that result in an SQL Injection vulnerability:
	 *
	 *     $wpdb->prepare( 'WHERE id = %1$s', $_GET['id'] ); // ?id=id
	 *
	 * So there may need to be a `_doing_it_wrong()` phase, after we know everyone can use
	 * identifier placeholders (%i), but before this feature is disabled or removed.
	 *
	 * @since 6.2.0
	 * @var bool
	 */
	private $allow_unsafe_unquoted_parameters = true;

/**
	 * Whether to use the mysqli extension over mysql. This is no longer used as the mysql
	 * extension is no longer supported.
	 *
	 * Default true.
	 *
	 * @since 3.9.0
	 * @since 6.4.0 This property was removed.
	 * @since 6.4.1 This property was reinstated and its default value was changed to true.
	 *              The property is no longer used in core but may be accessed externally.
	 *
	 * @var bool
	 */
	private $use_mysqli = true;

/**
	 * Whether we've managed to successfully connect at some point.
	 *
	 * @since 3.9.0
	 *
	 * @var bool
	 */
	private $has_connected = false;

/**
	 * Time when the last query was performed.
	 *
	 * Only set when `SAVEQUERIES` is defined and truthy.
	 *
	 * @since 1.5.0
	 *
	 * @var float
	 */
	public $time_start = null;

/**
	 * The last SQL error that was encountered.
	 *
	 * @since 2.5.0
	 *
	 * @var WP_Error|string
	 */
	public $error = null;

/**
	 * Connects to the database server and selects a database.
	 *
	 * Does the actual setting up
	 * of the class properties and connection to the database.
	 *
	 * @since 2.0.8
	 *
	 * @link https://core.trac.wordpress.org/ticket/3354
	 *
	 * @param string $dbuser     Database user.
	 * @param string $dbpassword Database password.
	 * @param string $dbname     Database name.
	 * @param string $dbhost     Database host.
	 */
	public function __construct(
		$dbuser,
		#[\SensitiveParameter]
		$dbpassword,
		$dbname,
		$dbhost
	) {
		if ( WP_DEBUG && WP_DEBUG_DISPLAY ) {
			$this->show_errors();
		}

$this->dbuser     = $dbuser;
		$this->dbpassword = $dbpassword;
		$this->dbname     = $dbname;
		$this->dbhost     = $dbhost;

// wp-config.php creation will manually connect when ready.
		if ( defined( 'WP_SETUP_CONFIG' ) ) {
			return;
		}

$this->db_connect();
	}

/**
	 * Makes private properties readable for backward compatibility.
	 *
	 * @since 3.5.0
	 *
	 * @param string $name The private member to get, and optionally process.
	 * @return mixed The private member.
	 */
	public function __get( $name ) {
		if ( 'col_info' === $name ) {
			$this->load_col_info();
		}

return $this->$name;
	}

/**
	 * Makes private properties settable for backward compatibility.
	 *
	 * @since 3.5.0
	 *
	 * @param string $name  The private member to set.
	 * @param mixed  $value The value to set.
	 */
	public function __set( $name, $value ) {
		$protected_members = array(
			'col_meta',
			'table_charset',
			'check_current_query',
			'allow_unsafe_unquoted_parameters',
		);
		if ( in_array( $name, $protected_members, true ) ) {
			return;
		}
		$this->$name = $value;
	}

/**
	 * Makes private properties check-able for backward compatibility.
	 *
	 * @since 3.5.0
	 *
	 * @param string $name The private member to check.
	 * @return bool If the member is set or not.
	 */
	public function __isset( $name ) {
		return isset( $this->$name );
	}

/**
	 * Makes private properties un-settable for backward compatibility.
	 *
	 * @since 3.5.0
	 *
	 * @param string $name The private member to unset.
	 */
	public function __unset( $name ) {
		unset( $this->$name );
	}

/**
	 * Sets $this->charset and $this->collate.
	 *
	 * @since 3.1.0
	 */
	public function init_charset() {
		$charset = '';
		$collate = '';

if ( function_exists( 'is_multisite' ) && is_multisite() ) {
			$charset = 'utf8';
			if ( defined( 'DB_COLLATE' ) && DB_COLLATE ) {
				$collate = DB_COLLATE;
			} else {
				$collate = 'utf8_general_ci';
			}
		} elseif ( defined( 'DB_COLLATE' ) ) {
			$collate = DB_COLLATE;
		}

if ( defined( 'DB_CHARSET' ) ) {
			$charset = DB_CHARSET;
		}

$charset_collate = $this->determine_charset( $charset, $collate );

$this->charset = $charset_collate['charset'];
		$this->collate = $charset_collate['collate'];
	}

/**
	 * Determines the best charset and collation to use given a charset and collation.
	 *
	 * For example, when able, utf8mb4 should be used instead of utf8.
	 *
	 * @since 4.6.0
	 *
	 * @param string $charset The character set to check.
	 * @param string $collate The collation to check.
	 * @return array {
	 *     The most appropriate character set and collation to use.
	 *
	 *     @type string $charset Character set.
	 *     @type string $collate Collation.
	 * }
	 */
	public function determine_charset( $charset, $collate ) {
		if ( ( ! ( $this->dbh instanceof mysqli ) ) || empty( $this->dbh ) ) {
			return compact( 'charset', 'collate' );
		}

if ( 'utf8' === $charset ) {
			$charset = 'utf8mb4';
		}

if ( 'utf8mb4' === $charset ) {
			// _general_ is outdated, so we can upgrade it to _unicode_, instead.
			if ( ! $collate || 'utf8_general_ci' === $collate ) {
				$collate = 'utf8mb4_unicode_ci';
			} else {
				$collate = str_replace( 'utf8_', 'utf8mb4_', $collate );
			}
		}

// _unicode_520_ is a better collation, we should use that when it's available.
		if ( $this->has_cap( 'utf8mb4_520' ) && 'utf8mb4_unicode_ci' === $collate ) {
			$collate = 'utf8mb4_unicode_520_ci';
		}

return compact( 'charset', 'collate' );
	}

/**
	 * Sets the connection's character set.
	 *
	 * @since 3.1.0
	 *
	 * @param mysqli $dbh     The connection returned by `mysqli_connect()`.
	 * @param string $charset Optional. The character set. Default null.
	 * @param string $collate Optional. The collation. Default null.
	 */
	public function set_charset( $dbh, $charset = null, $collate = null ) {
		if ( ! isset( $charset ) ) {
			$charset = $this->charset;
		}
		if ( ! isset( $collate ) ) {
			$collate = $this->collate;
		}
		if ( $this->has_cap( 'collation' ) && ! empty( $charset ) ) {
			$set_charset_succeeded = true;

if ( function_exists( 'mysqli_set_charset' ) && $this->has_cap( 'set_charset' ) ) {
				$set_charset_succeeded = mysqli_set_charset( $dbh, $charset );
			}

if ( $set_charset_succeeded ) {
				$query = $this->prepare( 'SET NAMES %s', $charset );
				if ( ! empty( $collate ) ) {
					$query .= $this->prepare( ' COLLATE %s', $collate );
				}
				mysqli_query( $dbh, $query );
			}
		}
	}

/**
	 * Changes the current SQL mode, and ensures its WordPress compatibility.
	 *
	 * If no modes are passed, it will ensure the current SQL server modes are compatible.
	 *
	 * @since 3.9.0
	 *
	 * @param array $modes Optional. A list of SQL modes to set. Default empty array.
	 */
	public function set_sql_mode( $modes = array() ) {
		if ( empty( $modes ) ) {
			$res = mysqli_query( $this->dbh, 'SELECT @@SESSION.sql_mode' );

if ( empty( $res ) ) {
				return;
			}

$modes_array = mysqli_fetch_array( $res );

if ( empty( $modes_array[0] ) ) {
				return;
			}

$modes = explode( ',', $modes_array[0] );
		}

$modes = array_change_key_case( $modes, CASE_UPPER );

/**
		 * Filters the list of incompatible SQL modes to exclude.
		 *
		 * @since 3.9.0
		 *
		 * @param array $incompatible_modes An array of incompatible modes.
		 */
		$incompatible_modes = (array) apply_filters( 'incompatible_sql_modes', $this->incompatible_modes );

foreach ( $modes as $i => $mode ) {
			if ( in_array( $mode, $incompatible_modes, true ) ) {
				unset( $modes[ $i ] );
			}
		}

$modes_str = implode( ',', $modes );

mysqli_query( $this->dbh, "SET SESSION sql_mode='$modes_str'" );
	}

/**
	 * Sets the table prefix for the WordPress tables.
	 *
	 * @since 2.5.0
	 *
	 * @param string $prefix          Alphanumeric name for the new prefix.
	 * @param bool   $set_table_names Optional. Whether the table names, e.g. wpdb::$posts,
	 *                                should be updated or not. Default true.
	 * @return string|WP_Error Old prefix or WP_Error on error.
	 */
	public function set_prefix( $prefix, $set_table_names = true ) {

if ( preg_match( '|[^a-z0-9_]|i', $prefix ) ) {
			return new WP_Error( 'invalid_db_prefix', 'Invalid database prefix' );
		}

$old_prefix = is_multisite() ? '' : $prefix;

if ( isset( $this->base_prefix ) ) {
			$old_prefix = $this->base_prefix;
		}

$this->base_prefix = $prefix;

if ( $set_table_names ) {
			foreach ( $this->tables( 'global' ) as $table => $prefixed_table ) {
				$this->$table = $prefixed_table;
			}

if ( is_multisite() && empty( $this->blogid ) ) {
				return $old_prefix;
			}

$this->prefix = $this->get_blog_prefix();

foreach ( $this->tables( 'blog' ) as $table => $prefixed_table ) {
				$this->$table = $prefixed_table;
			}

foreach ( $this->tables( 'old' ) as $table => $prefixed_table ) {
				$this->$table = $prefixed_table;
			}
		}
		return $old_prefix;
	}

/**
	 * Sets blog ID.
	 *
	 * @since 3.0.0
	 *
	 * @param int $blog_id
	 * @param int $network_id Optional. Network ID. Default 0.
	 * @return int Previous blog ID.
	 */
	public function set_blog_id( $blog_id, $network_id = 0 ) {
		if ( ! empty( $network_id ) ) {
			$this->siteid = $network_id;
		}

$old_blog_id  = $this->blogid;
		$this->blogid = $blog_id;

$this->prefix = $this->get_blog_prefix();

foreach ( $this->tables( 'blog' ) as $table => $prefixed_table ) {
			$this->$table = $prefixed_table;
		}

foreach ( $this->tables( 'old' ) as $table => $prefixed_table ) {
			$this->$table = $prefixed_table;
		}

return $old_blog_id;
	}

/**
	 * Gets blog prefix.
	 *
	 * @since 3.0.0
	 *
	 * @param int $blog_id Optional. Blog ID to retrieve the table prefix for.
	 *                     Defaults to the current blog ID.
	 * @return string Blog prefix.
	 */
	public function get_blog_prefix( $blog_id = null ) {
		if ( is_multisite() ) {
			if ( null === $blog_id ) {
				$blog_id = $this->blogid;
			}

$blog_id = (int) $blog_id;

if ( defined( 'MULTISITE' ) && ( 0 === $blog_id || 1 === $blog_id ) ) {
				return $this->base_prefix;
			} else {
				return $this->base_prefix . $blog_id . '_';
			}
		} else {
			return $this->base_prefix;
		}
	}

/**
	 * Returns an array of WordPress tables.
	 *
	 * Also allows for the `CUSTOM_USER_TABLE` and `CUSTOM_USER_META_TABLE` to override the WordPress users
	 * and usermeta tables that would otherwise be determined by the prefix.
	 *
	 * The `$scope` argument can take one of the following:
	 *
	 * - 'all' - returns 'all' and 'global' tables. No old tables are returned.
	 * - 'blog' - returns the blog-level tables for the queried blog.
	 * - 'global' - returns the global tables for the installation, returning multisite tables only on multisite.
	 * - 'ms_global' - returns the multisite global tables, regardless if current installation is multisite.
	 * - 'old' - returns tables which are deprecated.
	 *
	 * @since 3.0.0
	 * @since 6.1.0 `old` now includes deprecated multisite global tables only on multisite.
	 *
	 * @uses wpdb::$tables
	 * @uses wpdb::$old_tables
	 * @uses wpdb::$global_tables
	 * @uses wpdb::$ms_global_tables
	 * @uses wpdb::$old_ms_global_tables
	 *
	 * @param string $scope   Optional. Possible values include 'all', 'global', 'ms_global', 'blog',
	 *                        or 'old' tables. Default 'all'.
	 * @param bool   $prefix  Optional. Whether to include table prefixes. If blog prefix is requested,
	 *                        then the custom users and usermeta tables will be mapped. Default true.
	 * @param int    $blog_id Optional. The blog_id to prefix. Used only when prefix is requested.
	 *                        Defaults to `wpdb::$blogid`.
	 * @return string[] Table names. When a prefix is requested, the key is the unprefixed table name.
	 */
	public function tables( $scope = 'all', $prefix = true, $blog_id = 0 ) {
		switch ( $scope ) {
			case 'all':
				$tables = array_merge( $this->global_tables, $this->tables );
				if ( is_multisite() ) {
					$tables = array_merge( $tables, $this->ms_global_tables );
				}
				break;
			case 'blog':
				$tables = $this->tables;
				break;
			case 'global':
				$tables = $this->global_tables;
				if ( is_multisite() ) {
					$tables = array_merge( $tables, $this->ms_global_tables );
				}
				break;
			case 'ms_global':
				$tables = $this->ms_global_tables;
				break;
			case 'old':
				$tables = $this->old_tables;
				if ( is_multisite() ) {
					$tables = array_merge( $tables, $this->old_ms_global_tables );
				}
				break;
			default:
				return array();
		}

if ( $prefix ) {
			if ( ! $blog_id ) {
				$blog_id = $this->blogid;
			}
			$blog_prefix   = $this->get_blog_prefix( $blog_id );
			$base_prefix   = $this->base_prefix;
			$global_tables = array_merge( $this->global_tables, $this->ms_global_tables );
			foreach ( $tables as $k => $table ) {
				if ( in_array( $table, $global_tables, true ) ) {
					$tables[ $table ] = $base_prefix . $table;
				} else {
					$tables[ $table ] = $blog_prefix . $table;
				}
				unset( $tables[ $k ] );
			}

if ( isset( $tables['users'] ) && defined( 'CUSTOM_USER_TABLE' ) ) {
				$tables['users'] = CUSTOM_USER_TABLE;
			}

if ( isset( $tables['usermeta'] ) && defined( 'CUSTOM_USER_META_TABLE' ) ) {
				$tables['usermeta'] = CUSTOM_USER_META_TABLE;
			}
		}

return $tables;
	}

/**
	 * Selects a database using the current or provided database connection.
	 *
	 * The database name will be changed based on the current database connection.
	 * On failure, the execution will bail and display a DB error.
	 *
	 * @since 0.71
	 *
	 * @param string $db  Database name.
	 * @param mysqli $dbh Optional. Database connection.
	 *                    Defaults to the current database handle.
	 */
	public function select( $db, $dbh = null ) {
		if ( is_null( $dbh ) ) {
			$dbh = $this->dbh;
		}

$success = mysqli_select_db( $dbh, $db );

if ( ! $success ) {
			$this->ready = false;
			if ( ! did_action( 'template_redirect' ) ) {
				wp_load_translations_early();

$message = '<h1>' . __( 'Cannot select database' ) . "</h1>\n";

$message .= '<p>' . sprintf(
					/* translators: %s: Database name. */
					__( 'The database server could be connected to (which means your username and password is okay) but the %s database could not be selected.' ),
					'<code>' . htmlspecialchars( $db, ENT_QUOTES ) . '</code>'
				) . "</p>\n";

$message .= "<ul>\n";
				$message .= '<li>' . __( 'Are you sure it exists?' ) . "</li>\n";

$message .= '<li>' . sprintf(
					/* translators: 1: Database user, 2: Database name. */
					__( 'Does the user %1$s have permission to use the %2$s database?' ),
					'<code>' . htmlspecialchars( $this->dbuser, ENT_QUOTES ) . '</code>',
					'<code>' . htmlspecialchars( $db, ENT_QUOTES ) . '</code>'
				) . "</li>\n";

$message .= '<li>' . sprintf(
					/* translators: %s: Database name. */
					__( 'On some systems the name of your database is prefixed with your username, so it would be like <code>username_%1$s</code>. Could that be the problem?' ),
					htmlspecialchars( $db, ENT_QUOTES )
				) . "</li>\n";

$message .= "</ul>\n";

$message .= '<p>' . sprintf(
					/* translators: %s: Support forums URL. */
					__( 'If you do not know how to set up a database you should <strong>contact your host</strong>. If all else fails you may find help at the <a href="%s">WordPress support forums</a>.' ),
					__( 'https://wordpress.org/support/forums/' )
				) . "</p>\n";

$this->bail( $message, 'db_select_fail' );
			}
		}
	}

/**
	 * Do not use, deprecated.
	 *
	 * Use esc_sql() or wpdb::prepare() instead.
	 *
	 * @since 2.8.0
	 * @deprecated 3.6.0 Use wpdb::prepare()
	 * @see wpdb::prepare()
	 * @see esc_sql()
	 *
	 * @param string $data
	 * @return string
	 */
	public function _weak_escape( $data ) {
		if ( func_num_args() === 1 && function_exists( '_deprecated_function' ) ) {
			_deprecated_function( __METHOD__, '3.6.0', 'wpdb::prepare() or esc_sql()' );
		}
		return addslashes( $data );
	}

/**
	 * Real escape using mysqli_real_escape_string().
	 *
	 * @since 2.8.0
	 *
	 * @see mysqli_real_escape_string()
	 *
	 * @param string $data String to escape.
	 * @return string Escaped string.
	 */
	public function _real_escape( $data ) {
		if ( ! is_scalar( $data ) ) {
			return '';
		}

if ( $this->dbh ) {
			$escaped = mysqli_real_escape_string( $this->dbh, $data );
		} else {
			$class = get_class( $this );

wp_load_translations_early();
			/* translators: %s: Database access abstraction class, usually wpdb or a class extending wpdb. */
			_doing_it_wrong( $class, sprintf( __( '%s must set a database connection for use with escaping.' ), $class ), '3.6.0' );

$escaped = addslashes( $data );
		}

return $this->add_placeholder_escape( $escaped );
	}

/**
	 * Escapes data. Works on arrays.
	 *
	 * @since 2.8.0
	 *
	 * @uses wpdb::_real_escape()
	 *
	 * @param string|array $data Data to escape.
	 * @return string|array Escaped data, in the same type as supplied.
	 */
	public function _escape( $data ) {
		if ( is_array( $data ) ) {
			foreach ( $data as $k => $v ) {
				if ( is_array( $v ) ) {
					$data[ $k ] = $this->_escape( $v );
				} else {
					$data[ $k ] = $this->_real_escape( $v );
				}
			}
		} else {
			$data = $this->_real_escape( $data );
		}

return $data;
	}

/**
	 * Do not use, deprecated.
	 *
	 * Use esc_sql() or wpdb::prepare() instead.
	 *
	 * @since 0.71
	 * @deprecated 3.6.0 Use wpdb::prepare()
	 * @see wpdb::prepare()
	 * @see esc_sql()
	 *
	 * @param string|array $data Data to escape.
	 * @return string|array Escaped data, in the same type as supplied.
	 */
	public function escape( $data ) {
		if ( func_num_args() === 1 && function_exists( '_deprecated_function' ) ) {
			_deprecated_function( __METHOD__, '3.6.0', 'wpdb::prepare() or esc_sql()' );
		}
		if ( is_array( $data ) ) {
			foreach ( $data as $k => $v ) {
				if ( is_array( $v ) ) {
					$data[ $k ] = $this->escape( $v, 'recursive' );
				} else {
					$data[ $k ] = $this->_weak_escape( $v, 'internal' );
				}
			}
		} else {
			$data = $this->_weak_escape( $data, 'internal' );
		}

return $data;
	}

/**
	 * Escapes content by reference for insertion into the database, for security.
	 *
	 * @uses wpdb::_real_escape()
	 *
	 * @since 2.3.0
	 *
	 * @param string $data String to escape.
	 */
	public function escape_by_ref( &$data ) {
		if ( ! is_float( $data ) ) {
			$data = $this->_real_escape( $data );
		}
	}

/**
	 * Quotes an identifier such as a table or field name.
	 *
	 * @since 6.2.0
	 *
	 * @param string $identifier Identifier to escape.
	 * @return string Escaped identifier.
	 */
	public function quote_identifier( $identifier ) {
		return '`' . $this->_escape_identifier_value( $identifier ) . '`';
	}

/**
	 * Escapes an identifier value without adding the surrounding quotes.
	 *
	 * - Permitted characters in quoted identifiers include the full Unicode
	 *   Basic Multilingual Plane (BMP), except U+0000.
	 * - To quote the identifier itself, you need to double the character, e.g. `a``b`.
	 *
	 * @since 6.2.0
	 *
	 * @link https://dev.mysql.com/doc/refman/8.0/en/identifiers.html
	 *
	 * @param string $identifier Identifier to escape.
	 * @return string Escaped identifier.
	 */
	private function _escape_identifier_value( $identifier ) {
		return str_replace( '`', '``', $identifier );
	}

/**
	 * Prepares a SQL query for safe execution.
	 *
	 * Uses `sprintf()`-like syntax. The following placeholders can be used in the query string:
	 *
	 * - `%d` (integer)
	 * - `%f` (float)
	 * - `%s` (string)
	 * - `%i` (identifier, e.g. table/field names)
	 *
	 * All placeholders MUST be left unquoted in the query string. A corresponding argument
	 * MUST be passed for each placeholder.
	 *
	 * Note: There is one exception to the above: for compatibility with old behavior,
	 * numbered or formatted string placeholders (eg, `%1$s`, `%5s`) will not have quotes
	 * added by this function, so should be passed with appropriate quotes around them.
	 *
	 * Literal percentage signs (`%`) in the query string must be written as `%%`. Percentage wildcards
	 * (for example, to use in LIKE syntax) must be passed via a substitution argument containing
	 * the complete LIKE string, these cannot be inserted directly in the query string.
	 * Also see wpdb::esc_like().
	 *
	 * Arguments may be passed as individual arguments to the method, or as a single array
	 * containing all arguments. A combination of the two is not supported.
	 *
	 * Examples:
	 *
	 *     $wpdb->prepare(
	 *         "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d OR `other_field` LIKE %s",
	 *         array( 'foo', 1337, '%bar' )
	 *     );
	 *
	 *     $wpdb->prepare(
	 *         "SELECT DATE_FORMAT(`field`, '%%c') FROM `table` WHERE `column` = %s",
	 *         'foo'
	 *     );
	 *
	 *     $wpdb->prepare(
	 *         "SELECT * FROM %i WHERE %i = %s",
	 *         $table,
	 *         $field,
	 *         $value
	 *     );
	 *
	 * @since 2.3.0
	 * @since 5.3.0 Formalized the existing and already documented `...$args` parameter
	 *              by updating the function signature. The second parameter was changed
	 *              from `$args` to `...$args`.
	 * @since 6.2.0 Added `%i` for identifiers, e.g. table or field names.
	 *              Check support via `wpdb::has_cap( 'identifier_placeholders' )`.
	 *              This preserves compatibility with `sprintf()`, as the C version uses
	 *              `%d` and `$i` as a signed integer, whereas PHP only supports `%d`.
	 *
	 * @link https://www.php.net/sprintf Description of syntax.
	 *
	 * @param string      $query   Query statement with `sprintf()`-like placeholders.
	 * @param array|mixed $args    The array of variables to substitute into the query's placeholders
	 *                             if being called with an array of arguments, or the first variable
	 *                             to substitute into the query's placeholders if being called with
	 *                             individual arguments.
	 * @param mixed       ...$args Further variables to substitute into the query's placeholders
	 *                             if being called with individual arguments.
	 * @return string|void Sanitized query string, if there is a query to prepare.
	 */
	public function prepare( $query, ...$args ) {
		if ( is_null( $query ) ) {
			return;
		}

/*
		 * This is not meant to be foolproof -- but it will catch obviously incorrect usage.
		 *
		 * Note: str_contains() is not used here, as this file can be included
		 * directly outside of WordPress core, e.g. by HyperDB, in which case
		 * the polyfills from wp-includes/compat.php are not loaded.
		 */
		if ( false === strpos( $query, '%' ) ) {
			wp_load_translations_early();
			_doing_it_wrong(
				'wpdb::prepare',
				sprintf(
					/* translators: %s: wpdb::prepare() */
					__( 'The query argument of %s must have a placeholder.' ),
					'wpdb::prepare()'
				),
				'3.9.0'
			);
		}

/*
		 * Specify the formatting allowed in a placeholder. The following are allowed:
		 *
		 * - Sign specifier, e.g. $+d
		 * - Numbered placeholders, e.g. %1$s
		 * - Padding specifier, including custom padding characters, e.g. %05s, %'#5s
		 * - Alignment specifier, e.g. %05-s
		 * - Precision specifier, e.g. %.2f
		 */
		$allowed_format = '(?:[1-9][0-9]*[$])?[-+0-9]*(?: |0|\'.)?[-+0-9]*(?:\.[0-9]+)?';

/*
		 * If a %s placeholder already has quotes around it, removing the existing quotes
		 * and re-inserting them ensures the quotes are consistent.
		 *
		 * For backward compatibility, this is only applied to %s, and not to placeholders like %1$s,
		 * which are frequently used in the middle of longer strings, or as table name placeholders.
		 */
		$query = str_replace( "'%s'", '%s', $query ); // Strip any existing single quotes.
		$query = str_replace( '"%s"', '%s', $query ); // Strip any existing double quotes.

// Escape any unescaped percents (i.e. anything unrecognised).
		$query = preg_replace( "/%(?:%|$|(?!($allowed_format)?[sdfFi]))/", '%%\\1', $query );

// Extract placeholders from the query.
		$split_query = preg_split( "/(^|[^%]|(?:%%)+)(%(?:$allowed_format)?[sdfFi])/", $query, -1, PREG_SPLIT_DELIM_CAPTURE );

$split_query_count = count( $split_query );

/*
		 * Split always returns with 1 value before the first placeholder (even with $query = "%s"),
		 * then 3 additional values per placeholder.
		 */
		$placeholder_count = ( ( $split_query_count - 1 ) / 3 );

// If args were passed as an array, as in vsprintf(), move them up.
		$passed_as_array = ( isset( $args[0] ) && is_array( $args[0] ) && 1 === count( $args ) );
		if ( $passed_as_array ) {
			$args = $args[0];
		}

$new_query       = '';
		$key             = 2; // Keys 0 and 1 in $split_query contain values before the first placeholder.
		$arg_id          = 0;
		$arg_identifiers = array();
		$arg_strings     = array();

while ( $key < $split_query_count ) {
			$placeholder = $split_query[ $key ];

$format = substr( $placeholder, 1, -1 );
			$type   = substr( $placeholder, -1 );

if ( 'f' === $type && true === $this->allow_unsafe_unquoted_parameters
				/*
				 * Note: str_ends_with() is not used here, as this file can be included
				 * directly outside of WordPress core, e.g. by HyperDB, in which case
				 * the polyfills from wp-includes/compat.php are not loaded.
				 */
				&& '%' === substr( $split_query[ $key - 1 ], -1, 1 )
			) {

/*
				 * Before WP 6.2 the "force floats to be locale-unaware" RegEx didn't
				 * convert "%%%f" to "%%%F" (note the uppercase F).
				 * This was because it didn't check to see if the leading "%" was escaped.
				 * And because the "Escape any unescaped percents" RegEx used "[sdF]" in its
				 * negative lookahead assertion, when there was an odd number of "%", it added
				 * an extra "%", to give the fully escaped "%%%%f" (not a placeholder).
				 */

$s = $split_query[ $key - 2 ] . $split_query[ $key - 1 ];
				$k = 1;
				$l = strlen( $s );
				while ( $k <= $l && '%' === $s[ $l - $k ] ) {
					++$k;
				}

$placeholder = '%' . ( $k % 2 ? '%' : '' ) . $format . $type;

--$placeholder_count;

} else {

// Force floats to be locale-unaware.
				if ( 'f' === $type ) {
					$type        = 'F';
					$placeholder = '%' . $format . $type;
				}

if ( 'i' === $type ) {
					$placeholder = '`%' . $format . 's`';
					// Using a simple strpos() due to previous checking (e.g. $allowed_format).
					$argnum_pos = strpos( $format, '$' );

if ( false !== $argnum_pos ) {
						// sprintf() argnum starts at 1, $arg_id from 0.
						$arg_identifiers[] = ( ( (int) substr( $format, 0, $argnum_pos ) ) - 1 );
					} else {
						$arg_identifiers[] = $arg_id;
					}
				} elseif ( 'd' !== $type && 'F' !== $type ) {
					/*
					 * i.e. ( 's' === $type ), where 'd' and 'F' keeps $placeholder unchanged,
					 * and we ensure string escaping is used as a safe default (e.g. even if 'x').
					 */
					$argnum_pos = strpos( $format, '$' );

if ( false !== $argnum_pos ) {
						$arg_strings[] = ( ( (int) substr( $format, 0, $argnum_pos ) ) - 1 );
					} else {
						$arg_strings[] = $arg_id;
					}

/*
					 * Unquoted strings for backward compatibility (dangerous).
					 * First, "numbered or formatted string placeholders (eg, %1$s, %5s)".
					 * Second, if "%s" has a "%" before it, even if it's unrelated (e.g. "LIKE '%%%s%%'").
					 */
					if ( true !== $this->allow_unsafe_unquoted_parameters
						/*
						 * Note: str_ends_with() is not used here, as this file can be included
						 * directly outside of WordPress core, e.g. by HyperDB, in which case
						 * the polyfills from wp-includes/compat.php are not loaded.
						 */
						|| ( '' === $format && '%' !== substr( $split_query[ $key - 1 ], -1, 1 ) )
					) {
						$placeholder = "'%" . $format . "s'";
					}
				}
			}

// Glue (-2), any leading characters (-1), then the new $placeholder.
			$new_query .= $split_query[ $key - 2 ] . $split_query[ $key - 1 ] . $placeholder;

$key += 3;
			++$arg_id;
		}

// Replace $query; and add remaining $query characters, or index 0 if there were no placeholders.
		$query = $new_query . $split_query[ $key - 2 ];

$dual_use = array_intersect( $arg_identifiers, $arg_strings );

if ( count( $dual_use ) > 0 ) {
			wp_load_translations_early();

$used_placeholders = array();

$key    = 2;
			$arg_id = 0;
			// Parse again (only used when there is an error).
			while ( $key < $split_query_count ) {
				$placeholder = $split_query[ $key ];

$format = substr( $placeholder, 1, -1 );

$argnum_pos = strpos( $format, '$' );

if ( false !== $argnum_pos ) {
					$arg_pos = ( ( (int) substr( $format, 0, $argnum_pos ) ) - 1 );
				} else {
					$arg_pos = $arg_id;
				}

$used_placeholders[ $arg_pos ][] = $placeholder;

$key += 3;
				++$arg_id;
			}

$conflicts = array();
			foreach ( $dual_use as $arg_pos ) {
				$conflicts[] = implode( ' and ', $used_placeholders[ $arg_pos ] );
			}

_doing_it_wrong(
				'wpdb::prepare',
				sprintf(
					/* translators: %s: A list of placeholders found to be a problem. */
					__( 'Arguments cannot be prepared as both an Identifier and Value. Found the following conflicts: %s' ),
					implode( ', ', $conflicts )
				),
				'6.2.0'
			);

return;
		}

$args_count = count( $args );

if ( $args_count !== $placeholder_count ) {
			if ( 1 === $placeholder_count && $passed_as_array ) {
				/*
				 * If the passed query only expected one argument,
				 * but the wrong number of arguments was sent as an array, bail.
				 */
				wp_load_translations_early();
				_doing_it_wrong(
					'wpdb::prepare',
					__( 'The query only expected one placeholder, but an array of multiple placeholders was sent.' ),
					'4.9.0'
				);

return;
			} else {
				/*
				 * If we don't have the right number of placeholders,
				 * but they were passed as individual arguments,
				 * or we were expecting multiple arguments in an array, throw a warning.
				 */
				wp_load_translations_early();
				_doing_it_wrong(
					'wpdb::prepare',
					sprintf(
						/* translators: 1: Number of placeholders, 2: Number of arguments passed. */
						__( 'The query does not contain the correct number of placeholders (%1$d) for the number of arguments passed (%2$d).' ),
						$placeholder_count,
						$args_count
					),
					'4.8.3'
				);

/*
				 * If we don't have enough arguments to match the placeholders,
				 * return an empty string to avoid a fatal error on PHP 8.
				 */
				if ( $args_count < $placeholder_count ) {
					$max_numbered_placeholder = 0;

for ( $i = 2, $l = $split_query_count; $i < $l; $i += 3 ) {
						// Assume a leading number is for a numbered placeholder, e.g. '%3$s'.
						$argnum = (int) substr( $split_query[ $i ], 1 );

if ( $max_numbered_placeholder < $argnum ) {
							$max_numbered_placeholder = $argnum;
						}
					}

if ( ! $max_numbered_placeholder || $args_count < $max_numbered_placeholder ) {
						return '';
					}
				}
			}
		}

$args_escaped = array();

foreach ( $args as $i => $value ) {
			if ( in_array( $i, $arg_identifiers, true ) ) {
				$args_escaped[] = $this->_escape_identifier_value( $value );
			} elseif ( is_int( $value ) || is_float( $value ) ) {
				$args_escaped[] = $value;
			} else {
				if ( ! is_scalar( $value ) && ! is_null( $value ) ) {
					wp_load_translations_early();
					_doing_it_wrong(
						'wpdb::prepare',
						sprintf(
							/* translators: %s: Value type. */
							__( 'Unsupported value type (%s).' ),
							gettype( $value )
						),
						'4.8.2'
					);

// Preserving old behavior, where values are escaped as strings.
					$value = '';
				}

$args_escaped[] = $this->_real_escape( $value );
			}
		}

$query = vsprintf( $query, $args_escaped );

return $this->add_placeholder_escape( $query );
	}

/**
	 * First half of escaping for `LIKE` special characters `%` and `_` before preparing for SQL.
	 *
	 * Use this only before wpdb::prepare() or esc_sql(). Reversing the order is very bad for security.
	 *
	 * Example Prepared Statement:
	 *
	 *     $wild = '%';
	 *     $find = 'only 43% of planets';
	 *     $like = $wild . $wpdb->esc_like( $find ) . $wild;
	 *     $sql  = $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE post_content LIKE %s", $like );
	 *
	 * Example Escape Chain:
	 *
	 *     $sql  = esc_sql( $wpdb->esc_like( $input ) );
	 *
	 * @since 4.0.0
	 *
	 * @param string $text The raw text to be escaped. The input typed by the user
	 *                     should have no extra or deleted slashes.
	 * @return string Text in the form of a LIKE phrase. The output is not SQL safe.
	 *                Call wpdb::prepare() or wpdb::_real_escape() next.
	 */
	public function esc_like( $text ) {
		return addcslashes( $text, '_%\\' );
	}

/**
	 * Prints SQL/DB error.
	 *
	 * @since 0.71
	 *
	 * @global array $EZSQL_ERROR Stores error information of query and error string.
	 *
	 * @param string $str The error to display.
	 * @return void|false Void if the showing of errors is enabled, false if disabled.
	 */
	public function print_error( $str = '' ) {
		global $EZSQL_ERROR;

if ( ! $str ) {
			$str = mysqli_error( $this->dbh );
		}

$EZSQL_ERROR[] = array(
			'query'     => $this->last_query,
			'error_str' => $str,
		);

if ( $this->suppress_errors ) {
			return false;
		}

$caller = $this->get_caller();
		if ( $caller ) {
			// Not translated, as this will only appear in the error log.
			$error_str = sprintf( 'WordPress database error %1$s for query %2$s made by %3$s', $str, $this->last_query, $caller );
		} else {
			$error_str = sprintf( 'WordPress database error %1$s for query %2$s', $str, $this->last_query );
		}

error_log( $error_str );

// Are we showing errors?
		if ( ! $this->show_errors ) {
			return false;
		}

wp_load_translations_early();

// If there is an error then take note of it.
		if ( is_multisite() ) {
			$msg = sprintf(
				"%s [%s]\n%s\n",
				__( 'WordPress database error:' ),
				$str,
				$this->last_query
			);

if ( defined( 'ERRORLOGFILE' ) ) {
				error_log( $msg, 3, ERRORLOGFILE );
			}
			if ( defined( 'DIEONDBERROR' ) ) {
				wp_die( $msg );
			}
		} else {
			$str   = htmlspecialchars( $str, ENT_QUOTES );
			$query = htmlspecialchars( $this->last_query, ENT_QUOTES );

printf(
				'<div id="error"><p class="wpdberror"><strong>%s</strong> [%s]<br /><code>%s</code></p></div>',
				__( 'WordPress database error:' ),
				$str,
				$query
			);
		}
	}

/**
	 * Enables showing of database errors.
	 *
	 * This function should be used only to enable showing of errors.
	 * wpdb::hide_errors() should be used instead for hiding errors.
	 *
	 * @since 0.71
	 *
	 * @see wpdb::hide_errors()
	 *
	 * @param bool $show Optional. Whether to show errors. Default true.
	 * @return bool Whether showing of errors was previously active.
	 */
	public function show_errors( $show = true ) {
		$errors            = $this->show_errors;
		$this->show_errors = $show;
		return $errors;
	}

/**
	 * Disables showing of database errors.
	 *
	 * By default database errors are not shown.
	 *
	 * @since 0.71
	 *
	 * @see wpdb::show_errors()
	 *
	 * @return bool Whether showing of errors was previously active.
	 */
	public function hide_errors() {
		$show              = $this->show_errors;
		$this->show_errors = false;
		return $show;
	}

/**
	 * Enables or disables suppressing of database errors.
	 *
	 * By default database errors are suppressed.
	 *
	 * @since 2.5.0
	 *
	 * @see wpdb::hide_errors()
	 *
	 * @param bool $suppress Optional. Whether to suppress errors. Default true.
	 * @return bool Whether suppressing of errors was previously active.
	 */
	public function suppress_errors( $suppress = true ) {
		$errors                = $this->suppress_errors;
		$this->suppress_errors = (bool) $suppress;
		return $errors;
	}

/**
	 * Kills cached query results.
	 *
	 * @since 0.71
	 */
	public function flush() {
		$this->last_result   = array();
		$this->col_info      = null;
		$this->last_query    = null;
		$this->rows_affected = 0;
		$this->num_rows      = 0;
		$this->last_error    = '';

if ( $this->result instanceof mysqli_result ) {
			mysqli_free_result( $this->result );
			$this->result = null;

// Confidence check before using the handle.
			if ( empty( $this->dbh ) || ! ( $this->dbh instanceof mysqli ) ) {
				return;
			}

// Clear out any results from a multi-query.
			while ( mysqli_more_results( $this->dbh ) ) {
				mysqli_next_result( $this->dbh );
			}
		}
	}

/**
	 * Connects to and selects database.
	 *
	 * If `$allow_bail` is false, the lack of database connection will need to be handled manually.
	 *
	 * @since 3.0.0
	 * @since 3.9.0 $allow_bail parameter added.
	 *
	 * @param bool $allow_bail Optional. Allows the function to bail. Default true.
	 * @return bool True with a successful connection, false on failure.
	 */
	public function db_connect( $allow_bail = true ) {
		$this->is_mysql = true;

$client_flags = defined( 'MYSQL_CLIENT_FLAGS' ) ? MYSQL_CLIENT_FLAGS : 0;

/*
		 * Switch error reporting off because WordPress handles its own.
		 * This is due to the default value change from `MYSQLI_REPORT_OFF`
		 * to `MYSQLI_REPORT_ERROR|MYSQLI_REPORT_STRICT` in PHP 8.1.
		 */
		mysqli_report( MYSQLI_REPORT_OFF );

$this->dbh = mysqli_init();

$host    = $this->dbhost;
		$port    = null;
		$socket  = null;
		$is_ipv6 = false;

$host_data = $this->parse_db_host( $this->dbhost );
		if ( $host_data ) {
			list( $host, $port, $socket, $is_ipv6 ) = $host_data;
		}

/*
		 * If using the `mysqlnd` library, the IPv6 address needs to be enclosed
		 * in square brackets, whereas it doesn't while using the `libmysqlclient` library.
		 * @see https://bugs.php.net/bug.php?id=67563
		 */
		if ( $is_ipv6 && extension_loaded( 'mysqlnd' ) ) {
			$host = "[$host]";
		}

if ( WP_DEBUG ) {
			mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
		} else {
			// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged
			@mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
		}

if ( $this->dbh->connect_errno ) {
			$this->dbh = null;
		}

if ( ! $this->dbh && $allow_bail ) {
			wp_load_translations_early();

// Load custom DB error template, if present.
			if ( file_exists( WP_CONTENT_DIR . '/db-error.php' ) ) {
				require_once WP_CONTENT_DIR . '/db-error.php';
				die();
			}

$message = '<h1>' . __( 'Error establishing a database connection' ) . "</h1>\n";

$message .= '<p>' . sprintf(
				/* translators: 1: wp-config.php, 2: Database host. */
				__( 'This either means that the username and password information in your %1$s file is incorrect or that contact with the database server at %2$s could not be established. This could mean your host&#8217;s database server is down.' ),
				'<code>wp-config.php</code>',
				'<code>' . htmlspecialchars( $this->dbhost, ENT_QUOTES ) . '</code>'
			) . "</p>\n";

$message .= "<ul>\n";
			$message .= '<li>' . __( 'Are you sure you have the correct username and password?' ) . "</li>\n";
			$message .= '<li>' . __( 'Are you sure you have typed the correct hostname?' ) . "</li>\n";
			$message .= '<li>' . __( 'Are you sure the database server is running?' ) . "</li>\n";
			$message .= "</ul>\n";

$message .= '<p>' . sprintf(
				/* translators: %s: Support forums URL. */
				__( 'If you are unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href="%s">WordPress support forums</a>.' ),
				__( 'https://wordpress.org/support/forums/' )
			) . "</p>\n";

$this->bail( $message, 'db_connect_fail' );

return false;
		} elseif ( $this->dbh ) {
			if ( ! $this->has_connected ) {
				$this->init_charset();
			}

$this->has_connected = true;

$this->set_charset( $this->dbh );

$this->ready = true;
			$this->set_sql_mode();
			$this->select( $this->dbname, $this->dbh );

return true;
		}

return false;
	}

/**
	 * Parses the DB_HOST setting to interpret it for mysqli_real_connect().
	 *
	 * mysqli_real_connect() doesn't support the host param including a port or socket
	 * like mysql_connect() does. This duplicates how mysql_connect() detects a port
	 * and/or socket file.
	 *
	 * @since 4.9.0
	 *
	 * @param string $host The DB_HOST setting to parse.
	 * @return array|false {
	 *     Array containing the host, the port, the socket and
	 *     whether it is an IPv6 address, in that order.
	 *     False if the host couldn't be parsed.
	 *
	 *     @type string      $0 Host name.
	 *     @type string|null $1 Port.
	 *     @type string|null $2 Socket.
	 *     @type bool        $3 Whether it is an IPv6 address.
	 * }
	 */
	public function parse_db_host( $host ) {
		$socket  = null;
		$is_ipv6 = false;

// First peel off the socket parameter from the right, if it exists.
		$socket_pos = strpos( $host, ':/' );
		if ( false !== $socket_pos ) {
			$socket = substr( $host, $socket_pos + 1 );
			$host   = substr( $host, 0, $socket_pos );
		}

/*
		 * We need to check for an IPv6 address first.
		 * An IPv6 address will always contain at least two colons.
		 */
		if ( substr_count( $host, ':' ) > 1 ) {
			$pattern = '#^(?:\[)?(?P<host>[0-9a-fA-F:]+)(?:\]:(?P<port>[\d]+))?#';
			$is_ipv6 = true;
		} else {
			// We seem to be dealing with an IPv4 address.
			$pattern = '#^(?P<host>[^:/]*)(?::(?P<port>[\d]+))?#';
		}

$matches = array();
		$result  = preg_match( $pattern, $host, $matches );

if ( 1 !== $result ) {
			// Couldn't parse the address, bail.
			return false;
		}

$host = ! empty( $matches['host'] ) ? $matches['host'] : '';
		// Port cannot be a string; must be null or an integer.
		$port = ! empty( $matches['port'] ) ? absint( $matches['port'] ) : null;

return array( $host, $port, $socket, $is_ipv6 );
	}

/**
	 * Checks that the connection to the database is still up. If not, try to reconnect.
	 *
	 * If this function is unable to reconnect, it will forcibly die, or if called
	 * after the {@see 'template_redirect'} hook has been fired, return false instead.
	 *
	 * If `$allow_bail` is false, the lack of database connection will need to be handled manually.
	 *
	 * @since 3.9.0
	 *
	 * @param bool $allow_bail Optional. Allows the function to bail. Default true.
	 * @return bool|void True if the connection is up.
	 */
	public function check_connection( $allow_bail = true ) {
		// Check if the connection is alive.
		if ( ! empty( $this->dbh ) && mysqli_query( $this->dbh, 'DO 1' ) !== false ) {
			return true;
		}

$error_reporting = false;

// Disable warnings, as we don't want to see a multitude of "unable to connect" messages.
		if ( WP_DEBUG ) {
			$error_reporting = error_reporting();
			error_reporting( $error_reporting & ~E_WARNING );
		}

for ( $tries = 1; $tries <= $this->reconnect_retries; $tries++ ) {
			/*
			 * On the last try, re-enable warnings. We want to see a single instance
			 * of the "unable to connect" message on the bail() screen, if it appears.
			 */
			if ( $this->reconnect_retries === $tries && WP_DEBUG ) {
				error_reporting( $error_reporting );
			}

if ( $this->db_connect( false ) ) {
				if ( $error_reporting ) {
					error_reporting( $error_reporting );
				}

return true;
			}

sleep( 1 );
		}

/*
		 * If template_redirect has already happened, it's too late for wp_die()/dead_db().
		 * Let's just return and hope for the best.
		 */
		if ( did_action( 'template_redirect' ) ) {
			return false;
		}

if ( ! $allow_bail ) {
			return false;
		}

wp_load_translations_early();

$message = '<h1>' . __( 'Error reconnecting to the database' ) . "</h1>\n";

$message .= '<p>' . sprintf(
			/* translators: %s: Database host. */
			__( 'This means that the contact with the database server at %s was lost. This could mean your host&#8217;s database server is down.' ),
			'<code>' . htmlspecialchars( $this->dbhost, ENT_QUOTES ) . '</code>'
		) . "</p>\n";

$message .= "<ul>\n";
		$message .= '<li>' . __( 'Are you sure the database server is running?' ) . "</li>\n";
		$message .= '<li>' . __( 'Are you sure the database server is not under particularly heavy load?' ) . "</li>\n";
		$message .= "</ul>\n";

$message .= '<p>' . sprintf(
			/* translators: %s: Support forums URL. */
			__( 'If you are unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href="%s">WordPress support forums</a>.' ),
			__( 'https://wordpress.org/support/forums/' )
		) . "</p>\n";

// We weren't able to reconnect, so we better bail.
		$this->bail( $message, 'db_connect_fail' );

/*
		 * Call dead_db() if bail didn't die, because this database is no more.
		 * It has ceased to be (at least temporarily).
		 */
		dead_db();
	}

/**
	 * Performs a database query, using current database connection.
	 *
	 * More information can be found on the documentation page.
	 *
	 * @since 0.71
	 *
	 * @link https://developer.wordpress.org/reference/classes/wpdb/
	 *
	 * @param string $query Database query.
	 * @return int|bool Boolean true for CREATE, ALTER, TRUNCATE and DROP queries. Number of rows
	 *                  affected/selected for all other queries. Boolean false on error.
	 */
	public function query( $query ) {
		if ( ! $this->ready ) {
			$this->check_current_query = true;
			return false;
		}

/**
		 * Filters the database query.
		 *
		 * Some queries are made before the plugins have been loaded,
		 * and thus cannot be filtered with this method.
		 *
		 * @since 2.1.0
		 *
		 * @param string $query Database query.
		 */
		$query = apply_filters( 'query', $query );

if ( ! $query ) {
			$this->insert_id = 0;
			return false;
		}

$this->flush();

// Log how the function was called.
		$this->func_call = "\$db->query(\"$query\")";

// If we're writing to the database, make sure the query will write safely.
		if ( $this->check_current_query && ! $this->check_ascii( $query ) ) {
			$stripped_query = $this->strip_invalid_text_from_query( $query );
			/*
			 * strip_invalid_text_from_query() can perform queries, so we need
			 * to flush again, just to make sure everything is clear.
			 */
			$this->flush();
			if ( $stripped_query !== $query ) {
				$this->insert_id  = 0;
				$this->last_query = $query;

wp_load_translations_early();

$this->last_error = __( 'WordPress database error: Could not perform query because it contains invalid data.' );

return false;
			}
		}

$this->check_current_query = true;

// Keep track of the last query for debug.
		$this->last_query = $query;

$this->_do_query( $query );

// Database server has gone away, try to reconnect.
		$mysql_errno = 0;

if ( $this->dbh instanceof mysqli ) {
			$mysql_errno = mysqli_errno( $this->dbh );
		} else {
			/*
			 * $dbh is defined, but isn't a real connection.
			 * Something has gone horribly wrong, let's try a reconnect.
			 */
			$mysql_errno = 2006;
		}

if ( empty( $this->dbh ) || 2006 === $mysql_errno ) {
			if ( $this->check_connection() ) {
				$this->_do_query( $query );
			} else {
				$this->insert_id = 0;
				return false;
			}
		}

// If there is an error then take note of it.
		if ( $this->dbh instanceof mysqli ) {
			$this->last_error = mysqli_error( $this->dbh );
		} else {
			$this->last_error = __( 'Unable to retrieve the error message from the database server' );
		}

if ( $this->last_error ) {
			// Clear insert_id on a subsequent failed insert.
			if ( $this->insert_id && preg_match( '/^\s*(insert|replace)\s/i', $query ) ) {
				$this->insert_id = 0;
			}

$this->print_error();
			return false;
		}

if ( preg_match( '/^\s*(create|alter|truncate|drop)\s/i', $query ) ) {
			$return_val = $this->result;
		} elseif ( preg_match( '/^\s*(insert|delete|update|replace)\s/i', $query ) ) {
			$this->rows_affected = mysqli_affected_rows( $this->dbh );

// Take note of the insert_id.
			if ( preg_match( '/^\s*(insert|replace)\s/i', $query ) ) {
				$this->insert_id = mysqli_insert_id( $this->dbh );
			}

// Return number of rows affected.
			$return_val = $this->rows_affected;
		} else {
			$num_rows = 0;

if ( $this->result instanceof mysqli_result ) {
				while ( $row = mysqli_fetch_object( $this->result ) ) {
					$this->last_result[ $num_rows ] = $row;
					++$num_rows;
				}
			}

// Log and return the number of rows selected.
			$this->num_rows = $num_rows;
			$return_val     = $num_rows;
		}

return $return_val;
	}

/**
	 * Internal function to perform the mysqli_query() call.
	 *
	 * @since 3.9.0
	 *
	 * @see wpdb::query()
	 *
	 * @param string $query The query to run.
	 */
	private function _do_query( $query ) {
		if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
			$this->timer_start();
		}

if ( ! empty( $this->dbh ) ) {
			$this->result = mysqli_query( $this->dbh, $query );
		}

++$this->num_queries;

if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
			$this->log_query(
				$query,
				$this->timer_stop(),
				$this->get_caller(),
				$this->time_start,
				array()
			);
		}
	}

/**
	 * Logs query data.
	 *
	 * @since 5.3.0
	 *
	 * @param string $query           The query's SQL.
	 * @param float  $query_time      Total time spent on the query, in seconds.
	 * @param string $query_callstack Comma-separated list of the calling functions.
	 * @param float  $query_start     Unix timestamp of the time at the start of the query.
	 * @param array  $query_data      Custom query data.
	 */
	public function log_query( $query, $query_time, $query_callstack, $query_start, $query_data ) {
		/**
		 * Filters the custom data to log alongside a query.
		 *
		 * Caution should be used when modifying any of this data, it is recommended that any additional
		 * information you need to store about a query be added as a new associative array element.
		 *
		 * @since 5.3.0
		 *
		 * @param array  $query_data      Custom query data.
		 * @param string $query           The query's SQL.
		 * @param float  $query_time      Total time spent on the query, in seconds.
		 * @param string $query_callstack Comma-separated list of the calling functions.
		 * @param float  $query_start     Unix timestamp of the time at the start of the query.
		 */
		$query_data = apply_filters( 'log_query_custom_data', $query_data, $query, $query_time, $query_callstack, $query_start );

$this->queries[] = array(
			$query,
			$query_time,
			$query_callstack,
			$query_start,
			$query_data,
		);
	}

/**
	 * Generates and returns a placeholder escape string for use in queries returned by ::prepare().
	 *
	 * @since 4.8.3
	 *
	 * @return string String to escape placeholders.
	 */
	public function placeholder_escape() {
		static $placeholder;

if ( ! $placeholder ) {
			// Old WP installs may not have AUTH_SALT defined.
			$salt = defined( 'AUTH_SALT' ) && AUTH_SALT ? AUTH_SALT : (string) rand();

$placeholder = '{' . hash_hmac( 'sha256', uniqid( $salt, true ), $salt ) . '}';
		}

/*
		 * Add the filter to remove the placeholder escaper. Uses priority 0, so that anything
		 * else attached to this filter will receive the query with the placeholder string removed.
		 */
		if ( false === has_filter( 'query', array( $this, 'remove_placeholder_escape' ) ) ) {
			add_filter( 'query', array( $this, 'remove_placeholder_escape' ), 0 );
		}

return $placeholder;
	}

/**
	 * Adds a placeholder escape string, to escape anything that resembles a printf() placeholder.
	 *
	 * @since 4.8.3
	 *
	 * @param string $query The query to escape.
	 * @return string The query with the placeholder escape string inserted where necessary.
	 */
	public function add_placeholder_escape( $query ) {
		/*
		 * To prevent returning anything that even vaguely resembles a placeholder,
		 * we clobber every % we can find.
		 */
		return str_replace( '%', $this->placeholder_escape(), $query );
	}

/**
	 * Removes the placeholder escape strings from a query.
	 *
	 * @since 4.8.3
	 *
	 * @param string $query The query from which the placeholder will be removed.
	 * @return string The query with the placeholder removed.
	 */
	public function remove_placeholder_escape( $query ) {
		return str_replace( $this->placeholder_escape(), '%', $query );
	}

/**
	 * Inserts a row into the table.
	 *
	 * Examples:
	 *
	 *     $wpdb->insert(
	 *         'table',
	 *         array(
	 *             'column1' => 'foo',
	 *             'column2' => 'bar',
	 *         )
	 *     );
	 *     $wpdb->insert(
	 *         'table',
	 *         array(
	 *             'column1' => 'foo',
	 *             'column2' => 1337,
	 *         ),
	 *         array(
	 *             '%s',
	 *             '%d',
	 *         )
	 *     );
	 *
	 * @since 2.5.0
	 *
	 * @see wpdb::prepare()
	 * @see wpdb::$field_types
	 * @see wp_set_wpdb_vars()
	 *
	 * @param string          $table  Table name.
	 * @param array           $data   Data to insert (in column => value pairs).
	 *                                Both `$data` columns and `$data` values should be "raw" (neither should be SQL escaped).
	 *                                Sending a null value will cause the column to be set to NULL - the corresponding
	 *                                format is ignored in this case.
	 * @param string[]|string $format Optional. An array of formats to be mapped to each of the value in `$data`.
	 *                                If string, that format will be used for all of the values in `$data`.
	 *                                A format is one of '%d', '%f', '%s' (integer, float, string).
	 *                                If omitted, all values in `$data` will be treated as strings unless otherwise
	 *                                specified in wpdb::$field_types. Default null.
	 * @return int|false The number of rows inserted, or false on error.
	 */
	public function insert( $table, $data, $format = null ) {
		return $this->_insert_replace_helper( $table, $data, $format, 'INSERT' );
	}

/**
	 * Replaces a row in the table or inserts it if it does not exist, based on a PRIMARY KEY or a UNIQUE index.
	 *
	 * A REPLACE works exactly like an INSERT, except that if an old row in the table has the same value as a new row
	 * for a PRIMARY KEY or a UNIQUE index, the old row is deleted before the new row is inserted.
	 *
	 * Examples:
	 *
	 *     $wpdb->replace(
	 *         'table',
	 *         array(
	 *             'ID'      => 123,
	 *             'column1' => 'foo',
	 *             'column2' => 'bar',
	 *         )
	 *     );
	 *     $wpdb->replace(
	 *         'table',
	 *         array(
	 *             'ID'      => 456,
	 *             'column1' => 'foo',
	 *             'column2' => 1337,
	 *         ),
	 *         array(
	 *             '%d',
	 *             '%s',
	 *             '%d',
	 *         )
	 *     );
	 *
	 * @since 3.0.0
	 *
	 * @see wpdb::prepare()
	 * @see wpdb::$field_types
	 * @see wp_set_wpdb_vars()
	 *
	 * @param string          $table  Table name.
	 * @param array           $data   Data to insert (in column => value pairs).
	 *                                Both `$data` columns and `$data` values should be "raw" (neither should be SQL escaped).
	 *                                A primary key or unique index is required to perform a replace operation.
	 *                                Sending a null value will cause the column to be set to NULL - the corresponding
	 *                                format is ignored in this case.
	 * @param string[]|string $format Optional. An array of formats to be mapped to each of the value in `$data`.
	 *                                If string, that format will be used for all of the values in `$data`.
	 *                                A format is one of '%d', '%f', '%s' (integer, float, string).
	 *                                If omitted, all values in `$data` will be treated as strings unless otherwise
	 *                                specified in wpdb::$field_types. Default null.
	 * @return int|false The number of rows affected, or false on error.
	 */
	public function replace( $table, $data, $format = null ) {
		return $this->_insert_replace_helper( $table, $data, $format, 'REPLACE' );
	}

/**
	 * Helper function for insert and replace.
	 *
	 * Runs an insert or replace query based on `$type` argument.
	 *
	 * @since 3.0.0
	 *
	 * @see wpdb::prepare()
	 * @see wpdb::$field_types
	 * @see wp_set_wpdb_vars()
	 *
	 * @param string          $table  Table name.
	 * @param array           $data   Data to insert (in column => value pairs).
	 *                                Both `$data` columns and `$data` values should be "raw" (neither should be SQL escaped).
	 *                                Sending a null value will cause the column to be set to NULL - the corresponding
	 *                                format is ignored in this case.
	 * @param string[]|string $format Optional. An array of formats to be mapped to each of the value in `$data`.
	 *                                If string, that format will be used for all of the values in `$data`.
	 *                                A format is one of '%d', '%f', '%s' (integer, float, string).
	 *                                If omitted, all values in `$data` will be treated as strings unless otherwise
	 *                                specified in wpdb::$field_types. Default null.
	 * @param string          $type   Optional. Type of operation. Either 'INSERT' or 'REPLACE'.
	 *                                Default 'INSERT'.
	 * @return int|false The number of rows affected, or false on error.
	 */
	public function _insert_replace_helper( $table, $data, $format = null, $type = 'INSERT' ) {
		$this->insert_id = 0;

if ( ! in_array( strtoupper( $type ), array( 'REPLACE', 'INSERT' ), true ) ) {
			return false;
		}

$data = $this->process_fields( $table, $data, $format );
		if ( false === $data ) {
			return false;
		}

$formats = array();
		$values  = array();
		foreach ( $data as $value ) {
			if ( is_null( $value['value'] ) ) {
				$formats[] = 'NULL';
				continue;
			}

$formats[] = $value['format'];
			$values[]  = $value['value'];
		}

$fields  = '`' . implode( '`, `', array_keys( $data ) ) . '`';
		$formats = implode( ', ', $formats );

$sql = "$type INTO `$table` ($fields) VALUES ($formats)";

$this->check_current_query = false;
		return $this->query( $this->prepare( $sql, $values ) );
	}

/**
	 * Updates a row in the table.
	 *
	 * Examples:
	 *
	 *     $wpdb->update(
	 *         'table',
	 *         array(
	 *             'column1' => 'foo',
	 *             'column2' => 'bar',
	 *         ),
	 *         array(
	 *             'ID' => 1,
	 *         )
	 *     );
	 *     $wpdb->update(
	 *         'table',
	 *         array(
	 *             'column1' => 'foo',
	 *             'column2' => 1337,
	 *         ),
	 *         array(
	 *             'ID' => 1,
	 *         ),
	 *         array(
	 *             '%s',
	 *             '%d',
	 *         ),
	 *         array(
	 *             '%d',
	 *         )
	 *     );
	 *
	 * @since 2.5.0
	 *
	 * @see wpdb::prepare()
	 * @see wpdb::$field_types
	 * @see wp_set_wpdb_vars()
	 *
	 * @param string          $table        Table name.
	 * @param array           $data         Data to update (in column => value pairs).
	 *                                      Both $data columns and $data values should be "raw" (neither should be SQL escaped).
	 *                                      Sending a null value will cause the column to be set to NULL - the corresponding
	 *                                      format is ignored in this case.
	 * @param array           $where        A named array of WHERE clauses (in column => value pairs).
	 *                                      Multiple clauses will be joined with ANDs.
	 *                                      Both $where columns and $where values should be "raw".
	 *                                      Sending a null value will create an IS NULL comparison - the corresponding
	 *                                      format will be ignored in this case.
	 * @param string[]|string $format       Optional. An array of formats to be mapped to each of the values in $data.
	 *                                      If string, that format will be used for all of the values in $data.
	 *                                      A format is one of '%d', '%f', '%s' (integer, float, string).
	 *                                      If omitted, all values in $data will be treated as strings unless otherwise
	 *                                      specified in wpdb::$field_types. Default null.
	 * @param string[]|string $where_format Optional. An array of formats to be mapped to each of the values in $where.
	 *                                      If string, that format will be used for all of the items in $where.
	 *                                      A format is one of '%d', '%f', '%s' (integer, float, string).
	 *                                      If omitted, all values in $where will be treated as strings unless otherwise
	 *                                      specified in wpdb::$field_types. Default null.
	 * @return int|false The number of rows updated, or false on error.
	 */
	public function update( $table, $data, $where, $format = null, $where_format = null ) {
		if ( ! is_array( $data ) || ! is_array( $where ) ) {
			return false;
		}

$data = $this->process_fields( $table, $data, $format );
		if ( false === $data ) {
			return false;
		}
		$where = $this->process_fields( $table, $where, $where_format );
		if ( false === $where ) {
			return false;
		}

$fields     = array();
		$conditions = array();
		$values     = array();
		foreach ( $data as $field => $value ) {
			if ( is_null( $value['value'] ) ) {
				$fields[] = "`$field` = NULL";
				continue;
			}

$fields[] = "`$field` = " . $value['format'];
			$values[] = $value['value'];
		}
		foreach ( $where as $field => $value ) {
			if ( is_null( $value['value'] ) ) {
				$conditions[] = "`$field` IS NULL";
				continue;
			}

$conditions[] = "`$field` = " . $value['format'];
			$values[]     = $value['value'];
		}

$fields     = implode( ', ', $fields );
		$conditions = implode( ' AND ', $conditions );

$sql = "UPDATE `$table` SET $fields WHERE $conditions";

$this->check_current_query = false;
		return $this->query( $this->prepare( $sql, $values ) );
	}

/**
	 * Deletes a row in the table.
	 *
	 * Examples:
	 *
	 *     $wpdb->delete(
	 *         'table',
	 *         array(
	 *             'ID' => 1,
	 *         )
	 *     );
	 *     $wpdb->delete(
	 *         'table',
	 *         array(
	 *             'ID' => 1,
	 *         ),
	 *         array(
	 *             '%d',
	 *         )
	 *     );
	 *
	 * @since 3.4.0
	 *
	 * @see wpdb::prepare()
	 * @see wpdb::$field_types
	 * @see wp_set_wpdb_vars()
	 *
	 * @param string          $table        Table name.
	 * @param array           $where        A named array of WHERE clauses (in column => value pairs).
	 *                                      Multiple clauses will be joined with ANDs.
	 *                                      Both $where columns and $where values should be "raw".
	 *                                      Sending a null value will create an IS NULL comparison - the corresponding
	 *                                      format will be ignored in this case.
	 * @param string[]|string $where_format Optional. An array of formats to be mapped to each of the values in $where.
	 *                                      If string, that format will be used for all of the items in $where.
	 *                                      A format is one of '%d', '%f', '%s' (integer, float, string).
	 *                                      If omitted, all values in $data will be treated as strings unless otherwise
	 *                                      specified in wpdb::$field_types. Default null.
	 * @return int|false The number of rows deleted, or false on error.
	 */
	public function delete( $table, $where, $where_format = null ) {
		if ( ! is_array( $where ) ) {
			return false;
		}

$where = $this->process_fields( $table, $where, $where_format );
		if ( false === $where ) {
			return false;
		}

$conditions = array();
		$values     = array();
		foreach ( $where as $field => $value ) {
			if ( is_null( $value['value'] ) ) {
				$conditions[] = "`$field` IS NULL";
				continue;
			}

$conditions[] = "`$field` = " . $value['format'];
			$values[]     = $value['value'];
		}

$conditions = implode( ' AND ', $conditions );

$sql = "DELETE FROM `$table` WHERE $conditions";

$this->check_current_query = false;
		return $this->query( $this->prepare( $sql, $values ) );
	}

/**
	 * Processes arrays of field/value pairs and field formats.
	 *
	 * This is a helper method for wpdb's CRUD methods, which take field/value pairs
	 * for inserts, updates, and where clauses. This method first pairs each value
	 * with a format. Then it determines the charset of that field, using that
	 * to determine if any invalid text would be stripped. If text is stripped,
	 * then field processing is rejected and the query fails.
	 *
	 * @since 4.2.0
	 *
	 * @param string          $table  Table name.
	 * @param array           $data   Array of values keyed by their field names.
	 * @param string[]|string $format Formats or format to be mapped to the values in the data.
	 * @return array|false An array of fields that contain paired value and formats.
	 *                     False for invalid values.
	 */
	protected function process_fields( $table, $data, $format ) {
		$data = $this->process_field_formats( $data, $format );
		if ( false === $data ) {
			return false;
		}

$data = $this->process_field_charsets( $data, $table );
		if ( false === $data ) {
			return false;
		}

$data = $this->process_field_lengths( $data, $table );
		if ( false === $data ) {
			return false;
		}

$converted_data = $this->strip_invalid_text( $data );

if ( $data !== $converted_data ) {

$problem_fields = array();
			foreach ( $data as $field => $value ) {
				if ( $value !== $converted_data[ $field ] ) {
					$problem_fields[] = $field;
				}
			}

wp_load_translations_early();

if ( 1 === count( $problem_fields ) ) {
				$this->last_error = sprintf(
					/* translators: %s: Database field where the error occurred. */
					__( 'WordPress database error: Processing the value for the following field failed: %s. The supplied value may be too long or contains invalid data.' ),
					reset( $problem_fields )
				);
			} else {
				$this->last_error = sprintf(
					/* translators: %s: Database fields where the error occurred. */
					__( 'WordPress database error: Processing the values for the following fields failed: %s. The supplied values may be too long or contain invalid data.' ),
					implode( ', ', $problem_fields )
				);
			}

return false;
		}

return $data;
	}

/**
	 * Prepares arrays of value/format pairs as passed to wpdb CRUD methods.
	 *
	 * @since 4.2.0
	 *
	 * @param array           $data   Array of values keyed by their field names.
	 * @param string[]|string $format Formats or format to be mapped to the values in the data.
	 * @return array {
	 *     Array of values and formats keyed by their field names.
	 *
	 *     @type array ...$0 {
	 *         Value and format for this field.
	 *
	 *         @type mixed  $value  The value to be formatted.
	 *         @type string $format The format to be mapped to the value.
	 *     }
	 * }
	 */
	protected function process_field_formats( $data, $format ) {
		$formats          = (array) $format;
		$original_formats = $formats;

foreach ( $data as $field => $value ) {
			$value = array(
				'value'  => $value,
				'format' => '%s',
			);

if ( ! empty( $format ) ) {
				$value['format'] = array_shift( $formats );
				if ( ! $value['format'] ) {
					$value['format'] = reset( $original_formats );
				}
			} elseif ( isset( $this->field_types[ $field ] ) ) {
				$value['format'] = $this->field_types[ $field ];
			}

$data[ $field ] = $value;
		}

return $data;
	}

/**
	 * Adds field charsets to field/value/format arrays generated by wpdb::process_field_formats().
	 *
	 * @since 4.2.0
	 *
	 * @param array  $data {
	 *     Array of values and formats keyed by their field names,
	 *     as it comes from the wpdb::process_field_formats() method.
	 *
	 *     @type array ...$0 {
	 *         Value and format for this field.
	 *
	 *         @type mixed  $value  The value to be formatted.
	 *         @type string $format The format to be mapped to the value.
	 *     }
	 * }
	 * @param string $table Table name.
	 * @return array|false {
	 *     The same array of data with additional 'charset' keys, or false if
	 *     the charset for the table cannot be found.
	 *
	 *     @type array ...$0 {
	 *         Value, format, and charset for this field.
	 *
	 *         @type mixed        $value   The value to be formatted.
	 *         @type string       $format  The format to be mapped to the value.
	 *         @type string|false $charset The charset to be used for the value.
	 *     }
	 * }
	 */
	protected function process_field_charsets( $data, $table ) {
		foreach ( $data as $field => $value ) {
			if ( '%d' === $value['format'] || '%f' === $value['format'] ) {
				/*
				 * We can skip this field if we know it isn't a string.
				 * This checks %d/%f versus ! %s because its sprintf() could take more.
				 */
				$value['charset'] = false;
			} else {
				$value['charset'] = $this->get_col_charset( $table, $field );
				if ( is_wp_error( $value['charset'] ) ) {
					return false;
				}
			}

$data[ $field ] = $value;
		}

return $data;
	}

/**
	 * For string fields, records the maximum string length that field can safely save.
	 *
	 * @since 4.2.1
	 *
	 * @param array  $data {
	 *     Array of values, formats, and charsets keyed by their field names,
	 *     as it comes from the wpdb::process_field_charsets() method.
	 *
	 *     @type array ...$0 {
	 *         Value, format, and charset for this field.
	 *
	 *         @type mixed        $value   The value to be formatted.
	 *         @type string       $format  The format to be mapped to the value.
	 *         @type string|false $charset The charset to be used for the value.
	 *     }
	 * }
	 * @param string $table Table name.
	 * @return array|false {
	 *     The same array of data with additional 'length' keys, or false if
	 *     information for the table cannot be found.
	 *
	 *     @type array ...$0 {
	 *         Value, format, charset, and length for this field.
	 *
	 *         @type mixed        $value   The value to be formatted.
	 *         @type string       $format  The format to be mapped to the value.
	 *         @type string|false $charset The charset to be used for the value.
	 *         @type array|false  $length  {
	 *             Information about the maximum length of the value.
	 *             False if the column has no length.
	 *
	 *             @type string $type   One of 'byte' or 'char'.
	 *             @type int    $length The column length.
	 *         }
	 *     }
	 * }
	 */
	protected function process_field_lengths( $data, $table ) {
		foreach ( $data as $field => $value ) {
			if ( '%d' === $value['format'] || '%f' === $value['format'] ) {
				/*
				 * We can skip this field if we know it isn't a string.
				 * This checks %d/%f versus ! %s because its sprintf() could take more.
				 */
				$value['length'] = false;
			} else {
				$value['length'] = $this->get_col_length( $table, $field );
				if ( is_wp_error( $value['length'] ) ) {
					return false;
				}
			}

$data[ $field ] = $value;
		}

return $data;
	}

/**
	 * Retrieves one value from the database.
	 *
	 * Executes a SQL query and returns the value from the SQL result.
	 * If the SQL result contains more than one column and/or more than one row,
	 * the value in the column and row specified is returned. If $query is null,
	 * the value in the specified column and row from the previous SQL result is returned.
	 *
	 * @since 0.71
	 *
	 * @param string|null $query Optional. SQL query. Defaults to null, use the result from the previous query.
	 * @param int         $x     Optional. Column of value to return. Indexed from 0. Default 0.
	 * @param int         $y     Optional. Row of value to return. Indexed from 0. Default 0.
	 * @return string|null Database query result (as string), or null on failure.
	 */
	public function get_var( $query = null, $x = 0, $y = 0 ) {
		$this->func_call = "\$db->get_var(\"$query\", $x, $y)";

if ( $query ) {
			if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
				$this->check_current_query = false;
			}

$this->query( $query );
		}

// Extract var out of cached results based on x,y vals.
		if ( ! empty( $this->last_result[ $y ] ) ) {
			$values = array_values( get_object_vars( $this->last_result[ $y ] ) );
		}

// If there is a value return it, else return null.
		return ( isset( $values[ $x ] ) && '' !== $values[ $x ] ) ? $values[ $x ] : null;
	}

/**
	 * Retrieves one row from the database.
	 *
	 * Executes a SQL query and returns the row from the SQL result.
	 *
	 * @since 0.71
	 *
	 * @param string|null $query  SQL query.
	 * @param string      $output Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which
	 *                            correspond to an stdClass object, an associative array, or a numeric array,
	 *                            respectively. Default OBJECT.
	 * @param int         $y      Optional. Row to return. Indexed from 0. Default 0.
	 * @return array|object|null|void Database query result in format specified by $output or null on failure.
	 */
	public function get_row( $query = null, $output = OBJECT, $y = 0 ) {
		$this->func_call = "\$db->get_row(\"$query\",$output,$y)";

if ( $query ) {
			if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
				$this->check_current_query = false;
			}

$this->query( $query );
		} else {
			return null;
		}

if ( ! isset( $this->last_result[ $y ] ) ) {
			return null;
		}

if ( OBJECT === $output ) {
			return $this->last_result[ $y ] ? $this->last_result[ $y ] : null;
		} elseif ( ARRAY_A === $output ) {
			return $this->last_result[ $y ] ? get_object_vars( $this->last_result[ $y ] ) : null;
		} elseif ( ARRAY_N === $output ) {
			return $this->last_result[ $y ] ? array_values( get_object_vars( $this->last_result[ $y ] ) ) : null;
		} elseif ( OBJECT === strtoupper( $output ) ) {
			// Back compat for OBJECT being previously case-insensitive.
			return $this->last_result[ $y ] ? $this->last_result[ $y ] : null;
		} else {
			$this->print_error( ' $db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N' );
		}
	}

/**
	 * Retrieves one column from the database.
	 *
	 * Executes a SQL query and returns the column from the SQL result.
	 * If the SQL result contains more than one column, the column specified is returned.
	 * If $query is null, the specified column from the previous SQL result is returned.
	 *
	 * @since 0.71
	 *
	 * @param string|null $query Optional. SQL query. Defaults to previous query.
	 * @param int         $x     Optional. Column to return. Indexed from 0. Default 0.
	 * @return array Database query result. Array indexed from 0 by SQL result row number.
	 */
	public function get_col( $query = null, $x = 0 ) {
		if ( $query ) {
			if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
				$this->check_current_query = false;
			}

$this->query( $query );
		}

$new_array = array();
		// Extract the column values.
		if ( $this->last_result ) {
			for ( $i = 0, $j = count( $this->last_result ); $i < $j; $i++ ) {
				$new_array[ $i ] = $this->get_var( null, $x, $i );
			}
		}
		return $new_array;
	}

/**
	 * Retrieves an entire SQL result set from the database (i.e., many rows).
	 *
	 * Executes a SQL query and returns the entire SQL result.
	 *
	 * @since 0.71
	 *
	 * @param string $query  SQL query.
	 * @param string $output Optional. Any of ARRAY_A | ARRAY_N | OBJECT | OBJECT_K constants.
	 *                       With one of the first three, return an array of rows indexed
	 *                       from 0 by SQL result row number. Each row is an associative array
	 *                       (column => value, ...), a numerically indexed array (0 => value, ...),
	 *                       or an object ( ->column = value ), respectively. With OBJECT_K,
	 *                       return an associative array of row objects keyed by the value
	 *                       of each row's first column's value. Duplicate keys are discarded.
	 *                       Default OBJECT.
	 * @return array|object|null Database query results.
	 */
	public function get_results( $query = null, $output = OBJECT ) {
		$this->func_call = "\$db->get_results(\"$query\", $output)";

if ( $query ) {
			if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
				$this->check_current_query = false;
			}

$this->query( $query );
		} else {
			return null;
		}

$new_array = array();
		if ( OBJECT === $output ) {
			// Return an integer-keyed array of row objects.
			return $this->last_result;
		} elseif ( OBJECT_K === $output ) {
			/*
			 * Return an array of row objects with keys from column 1.
			 * (Duplicates are discarded.)
			 */
			if ( $this->last_result ) {
				foreach ( $this->last_result as $row ) {
					$var_by_ref = get_object_vars( $row );
					$key        = array_shift( $var_by_ref );
					if ( ! isset( $new_array[ $key ] ) ) {
						$new_array[ $key ] = $row;
					}
				}
			}
			return $new_array;
		} elseif ( ARRAY_A === $output || ARRAY_N === $output ) {
			// Return an integer-keyed array of...
			if ( $this->last_result ) {
				if ( ARRAY_N === $output ) {
					foreach ( (array) $this->last_result as $row ) {
						// ...integer-keyed row arrays.
						$new_array[] = array_values( get_object_vars( $row ) );
					}
				} else {
					foreach ( (array) $this->last_result as $row ) {
						// ...column name-keyed row arrays.
						$new_array[] = get_object_vars( $row );
					}
				}
			}
			return $new_array;
		} elseif ( strtoupper( $output ) === OBJECT ) {
			// Back compat for OBJECT being previously case-insensitive.
			return $this->last_result;
		}
		return null;
	}

/**
	 * Retrieves the character set for the given table.
	 *
	 * @since 4.2.0
	 *
	 * @param string $table Table name.
	 * @return string|WP_Error Table character set, WP_Error object if it couldn't be found.
	 */
	protected function get_table_charset( $table ) {
		$tablekey = strtolower( $table );

/**
		 * Filters the table charset value before the DB is checked.
		 *
		 * Returning a non-null value from the filter will effectively short-circuit
		 * checking the DB for the charset, returning that value instead.
		 *
		 * @since 4.2.0
		 *
		 * @param string|WP_Error|null $charset The character set to use, WP_Error object
		 *                                      if it couldn't be found. Default null.
		 * @param string               $table   The name of the table being checked.
		 */
		$charset = apply_filters( 'pre_get_table_charset', null, $table );
		if ( null !== $charset ) {
			return $charset;
		}

if ( isset( $this->table_charset[ $tablekey ] ) ) {
			return $this->table_charset[ $tablekey ];
		}

$charsets = array();
		$columns  = array();

$table_parts = explode( '.', $table );
		$table       = '`' . implode( '`.`', $table_parts ) . '`';
		$results     = $this->get_results( "SHOW FULL COLUMNS FROM $table" );
		if ( ! $results ) {
			return new WP_Error( 'wpdb_get_table_charset_failure', __( 'Could not retrieve table charset.' ) );
		}

foreach ( $results as $column ) {
			$columns[ strtolower( $column->Field ) ] = $column;
		}

$this->col_meta[ $tablekey ] = $columns;

foreach ( $columns as $column ) {
			if ( ! empty( $column->Collation ) ) {
				list( $charset ) = explode( '_', $column->Collation );

$charsets[ strtolower( $charset ) ] = true;
			}

list( $type ) = explode( '(', $column->Type );

// A binary/blob means the whole query gets treated like this.
			if ( in_array( strtoupper( $type ), array( 'BINARY', 'VARBINARY', 'TINYBLOB', 'MEDIUMBLOB', 'BLOB', 'LONGBLOB' ), true ) ) {
				$this->table_charset[ $tablekey ] = 'binary';
				return 'binary';
			}
		}

// utf8mb3 is an alias for utf8.
		if ( isset( $charsets['utf8mb3'] ) ) {
			$charsets['utf8'] = true;
			unset( $charsets['utf8mb3'] );
		}

// Check if we have more than one charset in play.
		$count = count( $charsets );
		if ( 1 === $count ) {
			$charset = key( $charsets );
		} elseif ( 0 === $count ) {
			// No charsets, assume this table can store whatever.
			$charset = false;
		} else {
			// More than one charset. Remove latin1 if present and recalculate.
			unset( $charsets['latin1'] );
			$count = count( $charsets );
			if ( 1 === $count ) {
				// Only one charset (besides latin1).
				$charset = key( $charsets );
			} elseif ( 2 === $count && isset( $charsets['utf8'], $charsets['utf8mb4'] ) ) {
				// Two charsets, but they're utf8 and utf8mb4, use utf8.
				$charset = 'utf8';
			} else {
				// Two mixed character sets. ascii.
				$charset = 'ascii';
			}
		}

$this->table_charset[ $tablekey ] = $charset;
		return $charset;
	}

/**
	 * Retrieves the character set for the given column.
	 *
	 * @since 4.2.0
	 *
	 * @param string $table  Table name.
	 * @param string $column Column name.
	 * @return string|false|WP_Error Column character set as a string. False if the column has
	 *                               no character set. WP_Error object if there was an error.
	 */
	public function get_col_charset( $table, $column ) {
		$tablekey  = strtolower( $table );
		$columnkey = strtolower( $column );

/**
		 * Filters the column charset value before the DB is checked.
		 *
		 * Passing a non-null value to the filter will short-circuit
		 * checking the DB for the charset, returning that value instead.
		 *
		 * @since 4.2.0
		 *
		 * @param string|null|false|WP_Error $charset The character set to use. Default null.
		 * @param string                     $table   The name of the table being checked.
		 * @param string                     $column  The name of the column being checked.
		 */
		$charset = apply_filters( 'pre_get_col_charset', null, $table, $column );
		if ( null !== $charset ) {
			return $charset;
		}

// Skip this entirely if this isn't a MySQL database.
		if ( empty( $this->is_mysql ) ) {
			return false;
		}

if ( empty( $this->table_charset[ $tablekey ] ) ) {
			// This primes column information for us.
			$table_charset = $this->get_table_charset( $table );
			if ( is_wp_error( $table_charset ) ) {
				return $table_charset;
			}
		}

// If still no column information, return the table charset.
		if ( empty( $this->col_meta[ $tablekey ] ) ) {
			return $this->table_charset[ $tablekey ];
		}

// If this column doesn't exist, return the table charset.
		if ( empty( $this->col_meta[ $tablekey ][ $columnkey ] ) ) {
			return $this->table_charset[ $tablekey ];
		}

// Return false when it's not a string column.
		if ( empty( $this->col_meta[ $tablekey ][ $columnkey ]->Collation ) ) {
			return false;
		}

list( $charset ) = explode( '_', $this->col_meta[ $tablekey ][ $columnkey ]->Collation );
		return $charset;
	}

/**
	 * Retrieves the maximum string length allowed in a given column.
	 *
	 * The length may either be specified as a byte length or a character length.
	 *
	 * @since 4.2.1
	 *
	 * @param string $table  Table name.
	 * @param string $column Column name.
	 * @return array|false|WP_Error {
	 *     Array of column length information, false if the column has no length (for
	 *     example, numeric column), WP_Error object if there was an error.
	 *
	 *     @type string $type   One of 'byte' or 'char'.
	 *     @type int    $length The column length.
	 * }
	 */
	public function get_col_length( $table, $column ) {
		$tablekey  = strtolower( $table );
		$columnkey = strtolower( $column );

// Skip this entirely if this isn't a MySQL database.
		if ( empty( $this->is_mysql ) ) {
			return false;
		}

if ( empty( $this->col_meta[ $tablekey ] ) ) {
			// This primes column information for us.
			$table_charset = $this->get_table_charset( $table );
			if ( is_wp_error( $table_charset ) ) {
				return $table_charset;
			}
		}

if ( empty( $this->col_meta[ $tablekey ][ $columnkey ] ) ) {
			return false;
		}

$typeinfo = explode( '(', $this->col_meta[ $tablekey ][ $columnkey ]->Type );

$type = strtolower( $typeinfo[0] );
		if ( ! empty( $typeinfo[1] ) ) {
			$length = trim( $typeinfo[1], ')' );
		} else {
			$length = false;
		}

switch ( $type ) {
			case 'char':
			case 'varchar':
				return array(
					'type'   => 'char',
					'length' => (int) $length,
				);

case 'binary':
			case 'varbinary':
				return array(
					'type'   => 'byte',
					'length' => (int) $length,
				);

case 'tinyblob':
			case 'tinytext':
				return array(
					'type'   => 'byte',
					'length' => 255,        // 2^8 - 1
				);

case 'blob':
			case 'text':
				return array(
					'type'   => 'byte',
					'length' => 65535,      // 2^16 - 1
				);

case 'mediumblob':
			case 'mediumtext':
				return array(
					'type'   => 'byte',
					'length' => 16777215,   // 2^24 - 1
				);

case 'longblob':
			case 'longtext':
				return array(
					'type'   => 'byte',
					'length' => 4294967295, // 2^32 - 1
				);

default:
				return false;
		}
	}

/**
	 * Checks if a string is ASCII.
	 *
	 * The negative regex is faster for non-ASCII strings, as it allows
	 * the search to finish as soon as it encounters a non-ASCII character.
	 *
	 * @since 4.2.0
	 *
	 * @param string $input_string String to check.
	 * @return bool True if ASCII, false if not.
	 */
	protected function check_ascii( $input_string ) {
		if ( function_exists( 'mb_check_encoding' ) ) {
			if ( mb_check_encoding( $input_string, 'ASCII' ) ) {
				return true;
			}
		} elseif ( ! preg_match( '/[^\x00-\x7F]/', $input_string ) ) {
			return true;
		}

return false;
	}

/**
	 * Checks if the query is accessing a collation considered safe.
	 *
	 * @since 4.2.0
	 *
	 * @param string $query The query to check.
	 * @return bool True if the collation is safe, false if it isn't.
	 */
	protected function check_safe_collation( $query ) {
		if ( $this->checking_collation ) {
			return true;
		}

// We don't need to check the collation for queries that don't read data.
		$query = ltrim( $query, "\r\n\t (" );
		if ( preg_match( '/^(?:SHOW|DESCRIBE|DESC|EXPLAIN|CREATE)\s/i', $query ) ) {
			return true;
		}

// All-ASCII queries don't need extra checking.
		if ( $this->check_ascii( $query ) ) {
			return true;
		}

$table = $this->get_table_from_query( $query );
		if ( ! $table ) {
			return false;
		}

$this->checking_collation = true;
		$collation                = $this->get_table_charset( $table );
		$this->checking_collation = false;

// Tables with no collation, or latin1 only, don't need extra checking.
		if ( false === $collation || 'latin1' === $collation ) {
			return true;
		}

$table = strtolower( $table );
		if ( empty( $this->col_meta[ $table ] ) ) {
			return false;
		}

// If any of the columns don't have one of these collations, it needs more confidence checking.
		$safe_collations = array(
			'utf8_bin',
			'utf8_general_ci',
			'utf8mb3_bin',
			'utf8mb3_general_ci',
			'utf8mb4_bin',
			'utf8mb4_general_ci',
		);

foreach ( $this->col_meta[ $table ] as $col ) {
			if ( empty( $col->Collation ) ) {
				continue;
			}

if ( ! in_array( $col->Collation, $safe_collations, true ) ) {
				return false;
			}
		}

return true;
	}

/**
	 * Strips any invalid characters based on value/charset pairs.
	 *
	 * @since 4.2.0
	 *
	 * @param array $data Array of value arrays. Each value array has the keys 'value', 'charset', and 'length'.
	 *                    An optional 'ascii' key can be set to false to avoid redundant ASCII checks.
	 * @return array|WP_Error The $data parameter, with invalid characters removed from each value.
	 *                        This works as a passthrough: any additional keys such as 'field' are
	 *                        retained in each value array. If we cannot remove invalid characters,
	 *                        a WP_Error object is returned.
	 */
	protected function strip_invalid_text( $data ) {
		$db_check_string = false;

foreach ( $data as &$value ) {
			$charset = $value['charset'];

if ( is_array( $value['length'] ) ) {
				$length                  = $value['length']['length'];
				$truncate_by_byte_length = 'byte' === $value['length']['type'];
			} else {
				$length = false;
				/*
				 * Since we have no length, we'll never truncate. Initialize the variable to false.
				 * True would take us through an unnecessary (for this case) codepath below.
				 */
				$truncate_by_byte_length = false;
			}

// There's no charset to work with.
			if ( false === $charset ) {
				continue;
			}

// Column isn't a string.
			if ( ! is_string( $value['value'] ) ) {
				continue;
			}

$needs_validation = true;
			if (
				// latin1 can store any byte sequence.
				'latin1' === $charset
			||
				// ASCII is always OK.
				( ! isset( $value['ascii'] ) && $this->check_ascii( $value['value'] ) )
			) {
				$truncate_by_byte_length = true;
				$needs_validation        = false;
			}

if ( $truncate_by_byte_length ) {
				mbstring_binary_safe_encoding();
				if ( false !== $length && strlen( $value['value'] ) > $length ) {
					$value['value'] = substr( $value['value'], 0, $length );
				}
				reset_mbstring_encoding();

if ( ! $needs_validation ) {
					continue;
				}
			}

// utf8 can be handled by regex, which is a bunch faster than a DB lookup.
			if ( ( 'utf8' === $charset || 'utf8mb3' === $charset || 'utf8mb4' === $charset ) && function_exists( 'mb_strlen' ) ) {
				$regex = '/
					(
						(?: [\x00-\x7F]                  # single-byte sequences   0xxxxxxx
						|   [\xC2-\xDF][\x80-\xBF]       # double-byte sequences   110xxxxx 10xxxxxx
						|   \xE0[\xA0-\xBF][\x80-\xBF]   # triple-byte sequences   1110xxxx 10xxxxxx * 2
						|   [\xE1-\xEC][\x80-\xBF]{2}
						|   \xED[\x80-\x9F][\x80-\xBF]
						|   [\xEE-\xEF][\x80-\xBF]{2}';

if ( 'utf8mb4' === $charset ) {
					$regex .= '
						|    \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences   11110xxx 10xxxxxx * 3
						|    [\xF1-\xF3][\x80-\xBF]{3}
						|    \xF4[\x80-\x8F][\x80-\xBF]{2}
					';
				}

$regex         .= '){1,40}                          # ...one or more times
					)
					| .                                  # anything else
					/x';
				$value['value'] = preg_replace( $regex, '$1', $value['value'] );

if ( false !== $length && mb_strlen( $value['value'], 'UTF-8' ) > $length ) {
					$value['value'] = mb_substr( $value['value'], 0, $length, 'UTF-8' );
				}
				continue;
			}

// We couldn't use any local conversions, send it to the DB.
			$value['db']     = true;
			$db_check_string = true;
		}
		unset( $value ); // Remove by reference.

if ( $db_check_string ) {
			$queries = array();
			foreach ( $data as $col => $value ) {
				if ( ! empty( $value['db'] ) ) {
					// We're going to need to truncate by characters or bytes, depending on the length value we have.
					if ( isset( $value['length']['type'] ) && 'byte' === $value['length']['type'] ) {
						// Using binary causes LEFT() to truncate by bytes.
						$charset = 'binary';
					} else {
						$charset = $value['charset'];
					}

if ( $this->charset ) {
						$connection_charset = $this->charset;
					} else {
						$connection_charset = mysqli_character_set_name( $this->dbh );
					}

if ( is_array( $value['length'] ) ) {
						$length          = sprintf( '%.0f', $value['length']['length'] );
						$queries[ $col ] = $this->prepare( "CONVERT( LEFT( CONVERT( %s USING $charset ), $length ) USING $connection_charset )", $value['value'] );
					} elseif ( 'binary' !== $charset ) {
						// If we don't have a length, there's no need to convert binary - it will always return the same result.
						$queries[ $col ] = $this->prepare( "CONVERT( CONVERT( %s USING $charset ) USING $connection_charset )", $value['value'] );
					}

unset( $data[ $col ]['db'] );
				}
			}

$sql = array();
			foreach ( $queries as $column => $query ) {
				if ( ! $query ) {
					continue;
				}

$sql[] = $query . " AS x_$column";
			}

$this->check_current_query = false;
			$row                       = $this->get_row( 'SELECT ' . implode( ', ', $sql ), ARRAY_A );
			if ( ! $row ) {
				return new WP_Error( 'wpdb_strip_invalid_text_failure', __( 'Could not strip invalid text.' ) );
			}

foreach ( array_keys( $data ) as $column ) {
				if ( isset( $row[ "x_$column" ] ) ) {
					$data[ $column ]['value'] = $row[ "x_$column" ];
				}
			}
		}

return $data;
	}

/**
	 * Strips any invalid characters from the query.
	 *
	 * @since 4.2.0
	 *
	 * @param string $query Query to convert.
	 * @return string|WP_Error The converted query, or a WP_Error object if the conversion fails.
	 */
	protected function strip_invalid_text_from_query( $query ) {
		// We don't need to check the collation for queries that don't read data.
		$trimmed_query = ltrim( $query, "\r\n\t (" );
		if ( preg_match( '/^(?:SHOW|DESCRIBE|DESC|EXPLAIN|CREATE)\s/i', $trimmed_query ) ) {
			return $query;
		}

$table = $this->get_table_from_query( $query );
		if ( $table ) {
			$charset = $this->get_table_charset( $table );
			if ( is_wp_error( $charset ) ) {
				return $charset;
			}

// We can't reliably strip text from tables containing binary/blob columns.
			if ( 'binary' === $charset ) {
				return $query;
			}
		} else {
			$charset = $this->charset;
		}

$data = array(
			'value'   => $query,
			'charset' => $charset,
			'ascii'   => false,
			'length'  => false,
		);

$data = $this->strip_invalid_text( array( $data ) );
		if ( is_wp_error( $data ) ) {
			return $data;
		}

return $data[0]['value'];
	}

/**
	 * Strips any invalid characters from the string for a given table and column.
	 *
	 * @since 4.2.0
	 *
	 * @param string $table  Table name.
	 * @param string $column Column name.
	 * @param string $value  The text to check.
	 * @return string|WP_Error The converted string, or a WP_Error object if the conversion fails.
	 */
	public function strip_invalid_text_for_column( $table, $column, $value ) {
		if ( ! is_string( $value ) ) {
			return $value;
		}

$charset = $this->get_col_charset( $table, $column );
		if ( ! $charset ) {
			// Not a string column.
			return $value;
		} elseif ( is_wp_error( $charset ) ) {
			// Bail on real errors.
			return $charset;
		}

$data = array(
			$column => array(
				'value'   => $value,
				'charset' => $charset,
				'length'  => $this->get_col_length( $table, $column ),
			),
		);

$data = $this->strip_invalid_text( $data );
		if ( is_wp_error( $data ) ) {
			return $data;
		}

return $data[ $column ]['value'];
	}

/**
	 * Finds the first table name referenced in a query.
	 *
	 * @since 4.2.0
	 *
	 * @param string $query The query to search.
	 * @return string|false The table name found, or false if a table couldn't be found.
	 */
	protected function get_table_from_query( $query ) {
		// Remove characters that can legally trail the table name.
		$query = rtrim( $query, ';/-#' );

// Allow (select...) union [...] style queries. Use the first query's table name.
		$query = ltrim( $query, "\r\n\t (" );

// Strip everything between parentheses except nested selects.
		$query = preg_replace( '/$(?!\s*select)[^(]*?$/is', '()', $query );

// Strip any leading SET STATEMENT statements.
		$query = preg_replace( '/^SET STATEMENT.+?\sFOR\s+/is', '', $query );

// Quickly match most common queries.
		if ( preg_match(
			'/^\s*(?:'
				. 'SELECT.*?\s+FROM'
				. '|INSERT(?:\s+LOW_PRIORITY|\s+DELAYED|\s+HIGH_PRIORITY)?(?:\s+IGNORE)?(?:\s+INTO)?'
				. '|REPLACE(?:\s+LOW_PRIORITY|\s+DELAYED)?(?:\s+INTO)?'
				. '|UPDATE(?:\s+LOW_PRIORITY)?(?:\s+IGNORE)?'
				. '|DELETE(?:\s+LOW_PRIORITY|\s+QUICK|\s+IGNORE)*(?:.+?FROM)?'
			. ')\s+((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)/is',
			$query,
			$maybe
		) ) {
			return str_replace( '`', '', $maybe[1] );
		}

// SHOW TABLE STATUS and SHOW TABLES WHERE Name = 'wp_posts'
		if ( preg_match( '/^\s*SHOW\s+(?:TABLE\s+STATUS|(?:FULL\s+)?TABLES).+WHERE\s+Name\s*=\s*("|\')((?:[0-9a-zA-Z$_.-]|[\xC2-\xDF][\x80-\xBF])+)\\1/is', $query, $maybe ) ) {
			return $maybe[2];
		}

/*
		 * SHOW TABLE STATUS LIKE and SHOW TABLES LIKE 'wp\_123\_%'
		 * This quoted LIKE operand seldom holds a full table name.
		 * It is usually a pattern for matching a prefix so we just
		 * strip the trailing % and unescape the _ to get 'wp_123_'
		 * which drop-ins can use for routing these SQL statements.
		 */
		if ( preg_match( '/^\s*SHOW\s+(?:TABLE\s+STATUS|(?:FULL\s+)?TABLES)\s+(?:WHERE\s+Name\s+)?LIKE\s*("|\')((?:[\\\\0-9a-zA-Z$_.-]|[\xC2-\xDF][\x80-\xBF])+)%?\\1/is', $query, $maybe ) ) {
			return str_replace( '\\_', '_', $maybe[2] );
		}

// Big pattern for the rest of the table-related queries.
		if ( preg_match(
			'/^\s*(?:'
				. '(?:EXPLAIN\s+(?:EXTENDED\s+)?)?SELECT.*?\s+FROM'
				. '|DESCRIBE|DESC|EXPLAIN|HANDLER'
				. '|(?:LOCK|UNLOCK)\s+TABLE(?:S)?'
				. '|(?:RENAME|OPTIMIZE|BACKUP|RESTORE|CHECK|CHECKSUM|ANALYZE|REPAIR).*\s+TABLE'
				. '|TRUNCATE(?:\s+TABLE)?'
				. '|CREATE(?:\s+TEMPORARY)?\s+TABLE(?:\s+IF\s+NOT\s+EXISTS)?'
				. '|ALTER(?:\s+IGNORE)?\s+TABLE'
				. '|DROP\s+TABLE(?:\s+IF\s+EXISTS)?'
				. '|CREATE(?:\s+\w+)?\s+INDEX.*\s+ON'
				. '|DROP\s+INDEX.*\s+ON'
				. '|LOAD\s+DATA.*INFILE.*INTO\s+TABLE'
				. '|(?:GRANT|REVOKE).*ON\s+TABLE'
				. '|SHOW\s+(?:.*FROM|.*TABLE)'
			. ')\s+$*\s*((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)\s*$*/is',
			$query,
			$maybe
		) ) {
			return str_replace( '`', '', $maybe[1] );
		}

return false;
	}

/**
	 * Loads the column metadata from the last query.
	 *
	 * @since 3.5.0
	 */
	protected function load_col_info() {
		if ( $this->col_info ) {
			return;
		}

$num_fields = mysqli_num_fields( $this->result );

for ( $i = 0; $i < $num_fields; $i++ ) {
			$this->col_info[ $i ] = mysqli_fetch_field( $this->result );
		}
	}

/**
	 * Retrieves column metadata from the last query.
	 *
	 * @since 0.71
	 *
	 * @param string $info_type  Optional. Possible values include 'name', 'table', 'def', 'max_length',
	 *                           'not_null', 'primary_key', 'multiple_key', 'unique_key', 'numeric',
	 *                           'blob', 'type', 'unsigned', 'zerofill'. Default 'name'.
	 * @param int    $col_offset Optional. 0: col name. 1: which table the col's in. 2: col's max length.
	 *                           3: if the col is numeric. 4: col's type. Default -1.
	 * @return mixed Column results.
	 */
	public function get_col_info( $info_type = 'name', $col_offset = -1 ) {
		$this->load_col_info();

if ( $this->col_info ) {
			if ( -1 === $col_offset ) {
				$i         = 0;
				$new_array = array();
				foreach ( (array) $this->col_info as $col ) {
					$new_array[ $i ] = $col->{$info_type};
					++$i;
				}
				return $new_array;
			} else {
				return $this->col_info[ $col_offset ]->{$info_type};
			}
		}
	}

/**
	 * Starts the timer, for debugging purposes.
	 *
	 * @since 1.5.0
	 *
	 * @return true
	 */
	public function timer_start() {
		$this->time_start = microtime( true );
		return true;
	}

/**
	 * Stops the debugging timer.
	 *
	 * @since 1.5.0
	 *
	 * @return float Total time spent on the query, in seconds.
	 */
	public function timer_stop() {
		return ( microtime( true ) - $this->time_start );
	}

/**
	 * Wraps errors in a nice header and footer and dies.
	 *
	 * Will not die if wpdb::$show_errors is false.
	 *
	 * @since 1.5.0
	 *
	 * @param string $message    The error message.
	 * @param string $error_code Optional. A computer-readable string to identify the error.
	 *                           Default '500'.
	 * @return void|false Void if the showing of errors is enabled, false if disabled.
	 */
	public function bail( $message, $error_code = '500' ) {
		if ( $this->show_errors ) {
			$error = '';

if ( $this->dbh instanceof mysqli ) {
				$error = mysqli_error( $this->dbh );
			} elseif ( mysqli_connect_errno() ) {
				$error = mysqli_connect_error();
			}

if ( $error ) {
				$message = '<p><code>' . $error . "</code></p>\n" . $message;
			}

wp_die( $message );
		} else {
			if ( class_exists( 'WP_Error', false ) ) {
				$this->error = new WP_Error( $error_code, $message );
			} else {
				$this->error = $message;
			}

return false;
		}
	}

/**
	 * Closes the current database connection.
	 *
	 * @since 4.5.0
	 *
	 * @return bool True if the connection was successfully closed,
	 *              false if it wasn't, or if the connection doesn't exist.
	 */
	public function close() {
		if ( ! $this->dbh ) {
			return false;
		}

$closed = mysqli_close( $this->dbh );

if ( $closed ) {
			$this->dbh           = null;
			$this->ready         = false;
			$this->has_connected = false;
		}

return $closed;
	}

/**
	 * Determines whether the database server is at least the required minimum version.
	 *
	 * @since 2.5.0
	 *
	 * @global string $required_mysql_version The minimum required MySQL version string.
	 * @return void|WP_Error
	 */
	public function check_database_version() {
		global $required_mysql_version;
		$wp_version = wp_get_wp_version();

// Make sure the server has the required MySQL version.
		if ( version_compare( $this->db_version(), $required_mysql_version, '<' ) ) {
			/* translators: 1: WordPress version number, 2: Minimum required MySQL version number. */
			return new WP_Error( 'database_version', sprintf( __( '<strong>Error:</strong> WordPress %1$s requires MySQL %2$s or higher' ), $wp_version, $required_mysql_version ) );
		}
	}

/**
	 * Determines whether the database supports collation.
	 *
	 * Called when WordPress is generating the table scheme.
	 *
	 * Use `wpdb::has_cap( 'collation' )`.
	 *
	 * @since 2.5.0
	 * @deprecated 3.5.0 Use wpdb::has_cap()
	 *
	 * @return bool True if collation is supported, false if not.
	 */
	public function supports_collation() {
		_deprecated_function( __FUNCTION__, '3.5.0', 'wpdb::has_cap( \'collation\' )' );
		return $this->has_cap( 'collation' );
	}

/**
	 * Retrieves the database character collate.
	 *
	 * @since 3.5.0
	 *
	 * @return string The database character collate.
	 */
	public function get_charset_collate() {
		$charset_collate = '';

if ( ! empty( $this->charset ) ) {
			$charset_collate = "DEFAULT CHARACTER SET $this->charset";
		}
		if ( ! empty( $this->collate ) ) {
			$charset_collate .= " COLLATE $this->collate";
		}

return $charset_collate;
	}

/**
	 * Determines whether the database or WPDB supports a particular feature.
	 *
	 * Capability sniffs for the database server and current version of WPDB.
	 *
	 * Database sniffs are based on the version of the database server in use.
	 *
	 * WPDB sniffs are added as new features are introduced to allow theme and plugin
	 * developers to determine feature support. This is to account for drop-ins which may
	 * introduce feature support at a different time to WordPress.
	 *
	 * @since 2.7.0
	 * @since 4.1.0 Added support for the 'utf8mb4' feature.
	 * @since 4.6.0 Added support for the 'utf8mb4_520' feature.
	 * @since 6.2.0 Added support for the 'identifier_placeholders' feature.
	 * @since 6.6.0 The `utf8mb4` feature now always returns true.
	 *
	 * @see wpdb::db_version()
	 *
	 * @param string $db_cap The feature to check for. Accepts 'collation', 'group_concat',
	 *                       'subqueries', 'set_charset', 'utf8mb4', 'utf8mb4_520',
	 *                       or 'identifier_placeholders'.
	 * @return bool True when the database feature is supported, false otherwise.
	 */
	public function has_cap( $db_cap ) {
		$db_version     = $this->db_version();
		$db_server_info = $this->db_server_info();

/*
		 * Account for MariaDB version being prefixed with '5.5.5-' on older PHP versions.
		 *
		 * Note: str_contains() is not used here, as this file can be included
		 * directly outside of WordPress core, e.g. by HyperDB, in which case
		 * the polyfills from wp-includes/compat.php are not loaded.
		 */
		if ( '5.5.5' === $db_version && false !== strpos( $db_server_info, 'MariaDB' )
			&& ( PHP_VERSION_ID <= 80015 // PHP 8.0.15 or older.
				|| 80100 <= PHP_VERSION_ID && PHP_VERSION_ID <= 80102 ) // PHP 8.1.0 to PHP 8.1.2.
		) {
			// Strip the '5.5.5-' prefix and set the version to the correct value.
			$db_server_info = preg_replace( '/^5\.5\.5-(.*)/', '$1', $db_server_info );
			$db_version     = preg_replace( '/[^0-9.].*/', '', $db_server_info );
		}

switch ( strtolower( $db_cap ) ) {
			case 'collation':    // @since 2.5.0
			case 'group_concat': // @since 2.7.0
			case 'subqueries':   // @since 2.7.0
				return version_compare( $db_version, '4.1', '>=' );
			case 'set_charset':
				return version_compare( $db_version, '5.0.7', '>=' );
			case 'utf8mb4':      // @since 4.1.0
				return true;
			case 'utf8mb4_520': // @since 4.6.0
				return version_compare( $db_version, '5.6', '>=' );
			case 'identifier_placeholders': // @since 6.2.0
				/*
				 * As of WordPress 6.2, wpdb::prepare() supports identifiers via '%i',
				 * e.g. table/field names.
				 */
				return true;
		}

return false;
	}

/**
	 * Retrieves a comma-separated list of the names of the functions that called wpdb.
	 *
	 * @since 2.5.0
	 *
	 * @return string Comma-separated list of the calling functions.
	 */
	public function get_caller() {
		return wp_debug_backtrace_summary( __CLASS__ );
	}

/**
	 * Retrieves the database server version number.
	 *
	 * @since 2.7.0
	 *
	 * @return string|null Version number on success, null on failure.
	 */
	public function db_version() {
		return preg_replace( '/[^0-9.].*/', '', $this->db_server_info() );
	}

/**
	 * Returns the raw version string of the database server.
	 *
	 * @since 5.5.0
	 *
	 * @return string Database server version as a string.
	 */
	public function db_server_info() {
		return mysqli_get_server_info( $this->dbh );
	}
}

Dosya Yükle

Archaeological Discoveries | Latest Finds & Breakthroughs – The Lost ERA

Discoveries

5000-Year-Old Dog Fossil Unearthed: Archaeologists Reveal New Clues About Early Human Life and Pet Domestication History

5000-Year-Old Dog Fossil : Archaeologists working on a routine dig in the rolling hills of Illinois stumbled upon something extraordinary last week—a nearly complete skeleton of a dog dating back ...

Mukesh Gusaiana

February 15, 2026

Archaeologists Lift 80-Tonne Stones Using Ancient Techniques, Unveiling Secrets of Megalithic Construction Methods Worldwide

Archaeologists Lift 80-Tonne Stones : In a groundbreaking discovery that’s captivating the nation, a team of archaeologists has successfully lifted massive 80-tonne stones from a submerged ancient site off the ...

Mukesh Gusaiana

February 15, 2026

Lost City of Alexander Resurfaces: Ancient Empire’s Frozen Secrets Unearthed Beneath February Polar Vortex in Astonishing Archaeological Discovery

Lost City of Alexander : Imagine stumbling upon a forgotten world right in your backyard, a place where ancient myths collide with modern soil. That’s exactly what happened when archaeologists ...

Mukesh Gusaiana

February 15, 2026

The Colour Beyond Sight: Scientists Just Created an “Impossible” New Colour That Only Five People Have Seen

The colour closest resembles a light teal: Imagine seeing a colour that does not exist in the natural world. A shade so pure, so saturated, that your brain has never ...

Mukesh Gusaiana

February 15, 2026

The Lost City of Alexander the Great: How Drones and Magnetometers Unveiled a 2,300-Year-Old Secret Beneath the Iraqi Desert

The Lost City of Alexander the Great: For over a millennium, it slept beneath the sand. A ghost city founded by history’s greatest conqueror, erased by floods, rebuilt by kings, ...

Mukesh Gusaiana

February 14, 2026

10,000 Years of History Unearthed at Newly Discovered Site in Egypt’s Sinai Peninsula

Irak Plateau in South Sinai: Deep in the remote desert of South Sinai, where the sun scorches the sandstone and the wind whispers across empty horizons, archaeologists have made a discovery ...

Mukesh Gusaiana

February 13, 2026

Archaeologists Discover a 4,000-Year-Old Kerma Grave in Sudan’s Bayuda Desert

4,000-Year-Old Kerma Grave in Sudan’s: The Lone Sentinel A 4,000-Year-Old Grave in Sudan’s Bayuda Desert Rewrites the Story of the Kerma Kingdom Some secrets refuse to stay buried. In the ...

Mukesh Gusaiana

February 13, 2026

Archaeologists Discover a Lost City Hidden Beneath the Desert for 1,200 Years

Imagine a city founded by Alexander the Great himself. A bustling port on the Tigris River. A crossroads of empires, destroyed by floods, rebuilt by kings, and eventually swallowed by ...

Mukesh Gusaiana

February 13, 2026

Archaeologists Identify Evidence of Tooth Blackening in 2,000-Year-Old Vietnamese Remains

Beauty leaves traces. Sometimes, those traces last for millennia. Archaeologists at the Dong Xa site in northern Vietnam have uncovered the oldest direct evidence of a striking tradition—intentional tooth blackening. ...

Mukesh Gusaiana

February 13, 2026

Prehistoric Human Skeletons Found in Karnataka’s Ballari, Revealing 5,000-Year-Old Burial Practices

Archaeologists have uncovered two prehistoric human skeletons during an ongoing excavation at Gaudra Moole Hill in Tekkalakote town of Karnataka’s Ballari district, offering rare insight into ancient burial customs and ...

Mukesh Gusaiana

February 9, 2026

123 4…9

The Lost ERA is a dedicated archaeology & history news site offering well-researched insights, discoveries, and educational articles on ancient civilizations, cultural heritage, and archaeological science. We strive to bring accurate historical reporting and engaging content to global readers.

Disclaimer

The Lost ERA provides research-based historical and archaeological content for educational purposes only. While we strive for accuracy, information may evolve with new discoveries. We are not responsible for external links or third-party content.

About Us

Editorial Policy

Publishing principles

Corrections & Updates