is_site_meta_supported(): bool
- Since
- 5.1.0
- Source
wp-includes/functions.php:6510
Description
This function checks whether the 'blogmeta' database table exists. The result is saved as a setting for the main network, making it essentially a global setting. Subsequent requests will refer to this setting instead of running the query.
Compatibility
- WordPress
- since 5.1.0
- 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.
Return value
bool- True if site meta is supported, false otherwise.
Performance profile
How much work a call to is_site_meta_supported() 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
- 5–33
- Plugin surface
- None
- Called by
- 4
Reaches the database via ->get_var().
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 35.
Nothing here hands control to plugin code.
4 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- optionnetwork option
get_network_option()called directly - sqldatabase query
->get_var()called directly - hookthird-party callbacks
apply_filters()one call below is_site_meta_supported() - cacheobject cache
wp_cache_get()one call below is_site_meta_supported() - serializeserialisation
maybe_unserialize()one call below is_site_meta_supported()
Further down the call graph this can also reach query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 3 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost is_site_meta_supported() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
!is_multisite() | 5 | is_multisite() |
is_multisite() && $supported !== false | 17 | is_multisite(), get_main_network_id(), get_network_option() |
is_multisite() && $supported === false | 32–33 | is_multisite(), get_main_network_id(), get_network_option(), ->get_var(), update_network_option() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 35 instructions, 5–33 executed per call, 3 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.
Uses · 4
- is_multisite()Determines whether Multisite is enabled.
- get_main_network_id()Gets the main network ID.
- get_network_option()Retrieves a network's option value based on the option name.
- update_network_option()Updates the value of a network option that was already added.
Used by · 4
- populate_site_meta()Creates WordPress site meta and sets the default values.
- upgrade_network()Executes network-level upgrade routines.
- wp_check_site_meta_support_prefilter()Aborts calls to site meta if it is not supported.
- wp_delete_site()Deletes a site from the database.
Source code
function is_site_meta_supported() { global $wpdb; if ( ! is_multisite() ) { return false; } $network_id = get_main_network_id(); $supported = get_network_option( $network_id, 'site_meta_supported', false ); if ( false === $supported ) { $supported = $wpdb->get_var( "SHOW TABLES LIKE '{$wpdb->blogmeta}'" ) ? 1 : 0; update_network_option( $network_id, 'site_meta_supported', $supported ); } return (bool) $supported;}Changelog
Introduced in 5.1.0. 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/functions.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.