delete_transient( string $transient ): bool
- Since
- 2.8.0
- Source
wp-includes/option.php:1380
Compatibility
- WordPress
- since 2.8.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$transientstring- Transient name. Expected to not be SQL-escaped.
Return value
bool- True if the transient was deleted, false otherwise.
Performance profile
How much work a call to delete_transient() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Moderate
- Scaling
- Constant
- Instructions
- 17–28
- Plugin surface
- 2 hooks
- Called by
- 14
Reads stored settings via delete_option(), cached per request but not free on a cold cache.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 34.
Third-party callbacks on 'delete_transient_{$transient}', 'deleted_transient' run inside this call, and their cost is not bounded by anything here.
14 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- transienttransient
delete_transient()this function does it - hookthird-party callbacks
do_action()called directly - cacheobject cache
wp_cache_delete()called directly - optionoption read or write
delete_option()called directly
Further down the call graph this can also reach serialize and query. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 7 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost delete_transient() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
wp_using_ext_object_cache() | 17 | do_action(), wp_using_ext_object_cache(), wp_cache_delete() |
!wp_using_ext_object_cache() && !wp_installing() | 20 | do_action(), wp_using_ext_object_cache(), wp_installing(), delete_option() |
!wp_using_ext_object_cache() && wp_installing() | 20 | do_action(), wp_using_ext_object_cache(), wp_installing(), wp_cache_delete() |
wp_using_ext_object_cache() | 21 | do_action(), wp_using_ext_object_cache(), wp_cache_delete(), do_action() |
!wp_using_ext_object_cache() && !wp_installing() | 24 | do_action(), wp_using_ext_object_cache(), wp_installing(), delete_option(), delete_option() |
!wp_using_ext_object_cache() && wp_installing() | 24 | do_action(), wp_using_ext_object_cache(), wp_installing(), wp_cache_delete(), do_action() |
!wp_using_ext_object_cache() && !wp_installing() | 28 | do_action(), wp_using_ext_object_cache(), wp_installing(), delete_option(), delete_option(), do_action() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 34 instructions, 17–28 executed per call, 4 branches. The work does not change between versions.
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Hooks and filters fired · 2
2 hooks fire while delete_transient() runs, in this order:
- do_action( delete_transient_{$transient} )actionline 1391 (+11 into the body)
Fires immediately before a specific transient is deleted.
- do_action( deleted_transient )actionline 1414 (+34 into the body)
Fires after a transient is deleted.
Uses · 5
- do_action()Calls the callback functions that have been added to an action hook.
- wp_using_ext_object_cache()Toggles `$_wp_using_ext_object_cache` on and off without directly touching global.
- wp_installing()Checks or sets whether WordPress is in "installation" mode.
- wp_cache_delete()Removes the cache contents matching key and group.
- delete_option()Removes an option by name. Prevents removal of protected WordPress options.
Used by · 14
- Featured_Content::delete_transient()Delete featured content IDs transient.
- WP_Automatic_Updater::has_fatal_error()Performs a loopback request to check for potential fatal errors.
- WP_Feed_Cache_Transient::unlink()Deletes transients.
- __clear_multi_author_cache()Helper function to clear the cache for number of authors.
- get_settings_errors()Fetches settings errors registered by add_settings_error().
- twentyfifteen_category_transient_flusher()Flush out the transients used in {@see twentyfifteen_categorized_blog()}.
- twentyfourteen_category_transient_flusher()Flush out the transients used in twentyfourteen_categorized_blog.
- twentyseventeen_category_transient_flusher()Flushes out the transients used in twentyseventeen_categorized_blog.
- twentysixteen_category_transient_flusher()Flushes out the transients used in twentysixteen_categorized_blog().
- upgrade_560()Executes changes made in WordPress 5.6.0.
- wp_dashboard_rss_control()Sets up the RSS dashboard widget control and $args to be used as input to wp_widget_rss_form().
- wp_edit_theme_plugin_file()Attempts to edit a file for a theme or plugin.
Show all 14
- wp_maybe_generate_attachment_metadata()Maybe attempts to generate attachment metadata, if missing.
- wp_upgrade()Runs WordPress Upgrade functions.
Source code
function delete_transient( $transient ) { /** * Fires immediately before a specific transient is deleted. * * The dynamic portion of the hook name, `$transient`, refers to the transient name. * * @since 3.0.0 * * @param string $transient Transient name. */ do_action( "delete_transient_{$transient}", $transient ); if ( wp_using_ext_object_cache() || wp_installing() ) { $result = wp_cache_delete( $transient, 'transient' ); } else { $option_timeout = '_transient_timeout_' . $transient; $option = '_transient_' . $transient; $result = delete_option( $option ); if ( $result ) { delete_option( $option_timeout ); } } if ( $result ) { /** * Fires after a transient is deleted. * * @since 3.0.0 * * @param string $transient Deleted transient name. */ do_action( 'deleted_transient', $transient ); } return $result;}Changelog
Introduced in 2.8.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 6.8.8 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
- Something wrong on this page? Report it and it gets fixed in the next regeneration.