WP_Site::get_instance( int $site_id ): WP_Site|false
- Since
- 4.5.0
- Source
wp-includes/class-wp-site.php:158
Compatibility
- WordPress
- since 4.5.0
- 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
$site_idint- The ID of the site to retrieve.
Return value
WP_Site|false- The site's object if found. False if not.
Performance profile
How much work a call to WP_Site::get_instance() 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
- Scaling
- Constant
- Instructions
- 6–42
- Plugin surface
- None
- Called by
- 3
Reaches the database via ->get_row().
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 44.
Nothing here hands control to plugin code.
3 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- cacheobject cache
wp_cache_get()called directly - sqldatabase query
->get_row()called directly - hookthird-party callbacks
do_action()one call below WP_Site::get_instance()
What one call costs · 4 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_Site::get_instance() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 6 | none |
$_site !== false | 15–18 | wp_cache_get() |
$_site === false && empty($_site) | 35–38 | wp_cache_get(), ->prepare(), ->get_row(), wp_cache_add() |
$_site === false && !empty($_site) | 38–42 | wp_cache_get(), ->prepare(), ->get_row(), is_wp_error(), wp_cache_add() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 44 | 6–42 | 5 | |
| 8.5 | 44 | 6–42 | 5 | |
| 8.4 | 44 | 6–42 | 5 | 2 fewer instructions than PHP 8.3 |
| 8.3 | 46 | 6–44 | 5 | |
| 8.2 | 46 | 6–44 | 5 | |
| 8.1 | 46 | 6–44 | 5 | |
| 7.4 | 46 | 6–44 | 5 |
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.
Uses · 4
- wp_cache_get()Retrieves the cache contents from the cache by key and group.
- is_wp_error()Checks whether the given variable is a WordPress Error.
- wp_cache_add()Adds data to the cache, if the cache key doesn't already exist.
- WP_Site::__construct()Creates a new WP_Site object.
Used by · 3
- WP_MS_Sites_List_Table::site_states()Determines whether to output comma-separated site states.
- get_blog_details()Retrieves the details for a blog from the blogs table and blog options.
- get_site()Retrieves site data given a site ID or site object.
Source code
public static function get_instance( $site_id ) { global $wpdb; $site_id = (int) $site_id; if ( ! $site_id ) { return false; } $_site = wp_cache_get( $site_id, 'sites' ); if ( false === $_site ) { $_site = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM {$wpdb->blogs} WHERE blog_id = %d LIMIT 1", $site_id ) ); if ( empty( $_site ) || is_wp_error( $_site ) ) { $_site = -1; } wp_cache_add( $site_id, $_site, 'sites' ); } if ( is_numeric( $_site ) ) { return false; } return new WP_Site( $_site ); }Changelog
Introduced in 4.5.0. 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 6.9.7 tag, from
src/wp-includes/class-wp-site.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.