delete_expired_transients( bool $force_db = false )

Description

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$force_dbbooloptional

Force cleanup to run against the database even when an external object cache is used.Default: false

Performance profile

How much work a call to delete_expired_transients() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Heavy

Reaches the database via ->query().

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

7–71

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 99.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

2

2 places in core call this, so the cost is paid more often than your own code shows.

What it touches

• sqldatabase query->query()called directly

Further down the call graph this can also reach hook. That is the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 11 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost delete_expired_transients() can have, taken from its control-flow graph on PHP 8.5.

Uses · 4

• wp_using_ext_object_cache()Toggles `$_wp_using_ext_object_cache` on and off without directly touching global.
• is_multisite()Determines whether Multisite is enabled.
• is_main_site()Determines whether a site is the main site of the current network.
• is_main_network()Determines whether a network is the main network of the Multisite installation.

Used by · 2

• populate_options()Create WordPress options and set the default values.
• upgrade_network()Executes network-level upgrade routines.

Source code

View on Trac ↗View on GitHub ↗

1617function delete_expired_transients( $force_db = false ) {1618	global $wpdb;1619 1620	if ( ! $force_db && wp_using_ext_object_cache() ) {1621		return;1622	}1623 1624	$wpdb->query(1625		$wpdb->prepare(1626			"DELETE a, b FROM {$wpdb->options} a, {$wpdb->options} b1627			WHERE a.option_name LIKE %s1628			AND a.option_name NOT LIKE %s1629			AND b.option_name = CONCAT( '_transient_timeout_', SUBSTRING( a.option_name, 12 ) )1630			AND b.option_value < %d",1631			$wpdb->esc_like( '_transient_' ) . '%',1632			$wpdb->esc_like( '_transient_timeout_' ) . '%',1633			time()1634		)1635	);1636 1637	if ( ! is_multisite() ) {1638		// Single site stores site transients in the options table.1639		$wpdb->query(1640			$wpdb->prepare(1641				"DELETE a, b FROM {$wpdb->options} a, {$wpdb->options} b1642				WHERE a.option_name LIKE %s1643				AND a.option_name NOT LIKE %s1644				AND b.option_name = CONCAT( '_site_transient_timeout_', SUBSTRING( a.option_name, 17 ) )1645				AND b.option_value < %d",1646				$wpdb->esc_like( '_site_transient_' ) . '%',1647				$wpdb->esc_like( '_site_transient_timeout_' ) . '%',1648				time()1649			)1650		);1651	} elseif ( is_multisite() && is_main_site() && is_main_network() ) {1652		// Multisite stores site transients in the sitemeta table.1653		$wpdb->query(1654			$wpdb->prepare(1655				"DELETE a, b FROM {$wpdb->sitemeta} a, {$wpdb->sitemeta} b1656				WHERE a.meta_key LIKE %s1657				AND a.meta_key NOT LIKE %s1658				AND b.meta_key = CONCAT( '_site_transient_timeout_', SUBSTRING( a.meta_key, 17 ) )1659				AND b.meta_value < %d",1660				$wpdb->esc_like( '_site_transient_' ) . '%',1661				$wpdb->esc_like( '_site_transient_timeout_' ) . '%',1662				time()1663			)1664		);1665	}1666}

Changelog

Introduced in 4.9.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 6.7.7 tag, from src/wp-includes/option.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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