delete_expired_transients( bool $force_db = false )

Deletes all expired transients.


Description Description

The multi-table delete syntax is used to delete the transient record from table a, and the corresponding transient_timeout record from table b.


Parameters Parameters

$force_db

(bool) (Optional) Force cleanup to run against the database even when an external object cache is used.

Default value: false


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Source Source

File: wp-includes/option.php

function delete_expired_transients( $force_db = false ) {
	global $wpdb;

	if ( ! $force_db && wp_using_ext_object_cache() ) {
		return;
	}

	$wpdb->query( $wpdb->prepare(
		"DELETE a, b FROM {$wpdb->options} a, {$wpdb->options} b
			WHERE a.option_name LIKE %s
			AND a.option_name NOT LIKE %s
			AND b.option_name = CONCAT( '_transient_timeout_', SUBSTRING( a.option_name, 12 ) )
			AND b.option_value < %d",
		$wpdb->esc_like( '_transient_' ) . '%',
		$wpdb->esc_like( '_transient_timeout_' ) . '%',
		time()
	) );

	if ( ! is_multisite() ) {
		// non-Multisite stores site transients in the options table.
		$wpdb->query( $wpdb->prepare(
			"DELETE a, b FROM {$wpdb->options} a, {$wpdb->options} b
				WHERE a.option_name LIKE %s
				AND a.option_name NOT LIKE %s
				AND b.option_name = CONCAT( '_site_transient_timeout_', SUBSTRING( a.option_name, 17 ) )
				AND b.option_value < %d",
			$wpdb->esc_like( '_site_transient_' ) . '%',
			$wpdb->esc_like( '_site_transient_timeout_' ) . '%',
			time()
		) );
	} elseif ( is_multisite() && is_main_site() && is_main_network() ) {
		// Multisite stores site transients in the sitemeta table.
		$wpdb->query( $wpdb->prepare(
			"DELETE a, b FROM {$wpdb->sitemeta} a, {$wpdb->sitemeta} b
				WHERE a.meta_key LIKE %s
				AND a.meta_key NOT LIKE %s
				AND b.meta_key = CONCAT( '_site_transient_timeout_', SUBSTRING( a.meta_key, 17 ) )
				AND b.meta_value < %d",
			$wpdb->esc_like( '_site_transient_' ) . '%',
			$wpdb->esc_like( '_site_transient_timeout_' ) . '%',
			time()
		) );
	}
}

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Changelog Changelog

Changelog
Version Description
4.9.0 Introduced.


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