wp_set_post_terms( int $post_id = 0, string|array $terms = '', string $taxonomy = 'post_tag', bool $append = false ): array|false|WP_Error
- Since
- 2.8.0
- Source
wp-includes/post.php:5713
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
$post_idintoptional- The Post ID. Does not default to the ID of the global $post.Default:
0 $termsstring|arrayoptional- An array of terms to set for the post, or a string of terms separated by commas. Hierarchical taxonomies must always pass IDs rather than names so that children with the same names but different parents aren't confused. Default empty.Default:
'' $taxonomystringoptional- Taxonomy name. Default 'post_tag'.Default:
'post_tag' $appendbooloptional- If true, don't delete existing terms, just add on. If false, replace the terms with the new terms. Default false.Default:
false
Return value
array|false|WP_Error- Array of term taxonomy IDs of affected terms. WP_Error or false on failure.
Performance profile
How much work a call to wp_set_post_terms() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Heavy
- Scaling
- Constant
- Instructions
- 8–47
- Plugin surface
- None
- Called by
- 6
Reaches the database via wp_get_object_terms().
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 48.
Nothing here hands control to plugin code.
6 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- querycontent query
wp_get_object_terms()one call below wp_set_post_terms() - hookthird-party callbacks
do_action()one call below wp_set_post_terms() - cacheobject cache
wp_cache_delete()one call below wp_set_post_terms()
Further down the call graph this can also reach option, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 5 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_set_post_terms() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 8 | none |
is_array($terms) && !is_taxonomy_hierarchical() | 22–23 | is_taxonomy_hierarchical(), wp_set_object_terms() |
is_array($terms) && is_taxonomy_hierarchical() | 30–31 | is_taxonomy_hierarchical(), array_map(), array_unique(), wp_set_object_terms() |
!is_array($terms) && !is_taxonomy_hierarchical() | 35–39 | _x(), explode(), is_taxonomy_hierarchical(), wp_set_object_terms() |
!is_array($terms) && is_taxonomy_hierarchical() | 43–47 | _x(), explode(), is_taxonomy_hierarchical(), array_map(), array_unique(), wp_set_object_terms() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 48 | 8–47 | 5 | |
| 8.5 | 48 | 8–47 | 5 | |
| 8.4 | 48 | 8–47 | 5 | 6 fewer instructions than PHP 8.3 |
| 8.3 | 54 | 8–53 | 5 | |
| 8.2 | 54 | 8–53 | 5 | |
| 8.1 | 54 | 8–53 | 5 | |
| 7.4 | 54 | 8–53 | 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 · 3
- _x()Retrieves translated string with gettext context.
- is_taxonomy_hierarchical()Determines whether the taxonomy object is hierarchical.
- wp_set_object_terms()Creates term and taxonomy relationships.
Used by · 6
- set_post_format()Assign a format to a post
- wp_insert_post()Inserts or update a post.
- wp_publish_post()Publishes a post by transitioning the post status.
- wp_set_post_categories()Sets categories for a post.
- wp_set_post_tags()Sets the tags for a post.
- wp_set_unique_slug_on_create_template_part()Sets a custom slug when creating auto-draft template parts.
Source code
function wp_set_post_terms( $post_id = 0, $terms = '', $taxonomy = 'post_tag', $append = false ) { $post_id = (int) $post_id; if ( ! $post_id ) { return false; } if ( empty( $terms ) ) { $terms = array(); } if ( ! is_array( $terms ) ) { $comma = _x( ',', 'tag delimiter' ); if ( ',' !== $comma ) { $terms = str_replace( $comma, ',', $terms ); } $terms = explode( ',', trim( $terms, " \n\t\r\0\x0B," ) ); } /* * Hierarchical taxonomies must always pass IDs rather than names so that * children with the same names but different parents aren't confused. */ if ( is_taxonomy_hierarchical( $taxonomy ) ) { $terms = array_unique( array_map( 'intval', $terms ) ); } return wp_set_object_terms( $post_id, $terms, $taxonomy, $append );}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 6.9.7 tag, from
src/wp-includes/post.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.