wppaste
WordPress

get_the_terms( int|WP_Post $post, string $taxonomy ): WP_Term[]|false|WP_Error

Since
2.5.0
Source
wp-includes/category-template.php:1288
Retrieves the terms of the taxonomy that are attached to the post.

Compatibility

WordPress
since 2.5.0
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

$postint|WP_Post
Post ID or object.
$taxonomystring
Taxonomy name.

Return value

WP_Term[]|false|WP_Error
Array of WP_Term objects on success, false if there are no terms or the post does not exist, WP_Error on failure.

Performance profile

How much work a call to get_the_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

Reaches the database via get_post().

Scaling
Constant

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

Instructions
8–52

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 54.

Plugin surface
1 hook

Third-party callbacks on 'get_the_terms' run inside this call, and their cost is not bounded by anything here.

Called by
16

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

What it touches

  • querycontent queryget_post()called directly
  • cacheobject cachewp_cache_add()called directly
  • hookthird-party callbacksapply_filters()called directly

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 · 4 distinct outcomes

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

WhenInstructionsCalls it makes
always8get_post()
$terms !== false28get_post(), get_object_term_cache(), apply_filters()
$terms === false && is_wp_error()39get_post(), get_object_term_cache(), wp_get_object_terms(), is_wp_error(), apply_filters()
$terms === false && !is_wp_error()52get_post(), get_object_term_cache(), wp_get_object_terms(), is_wp_error(), wp_list_pluck(), wp_cache_add(), apply_filters()

Across PHP versions

Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 54 instructions, 8–52 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 · 1

One hook fires while get_the_terms() runs, in this order:

  1. apply_filters( get_the_terms )filterline 1314 (+26 into the body)

    Filters the list of terms attached to the given post.

Uses · 7

Used by · 16

Show all 16

Source code

function get_the_terms( $post, $taxonomy ) {	$post = get_post( $post ); 	if ( ! $post ) {		return false;	} 	$terms = get_object_term_cache( $post->ID, $taxonomy ); 	if ( false === $terms ) {		$terms = wp_get_object_terms( $post->ID, $taxonomy );		if ( ! is_wp_error( $terms ) ) {			$term_ids = wp_list_pluck( $terms, 'term_id' );			wp_cache_add( $post->ID, $term_ids, $taxonomy . '_relationships' );		}	} 	/**	 * Filters the list of terms attached to the given post.	 *	 * @since 3.1.0	 *	 * @param WP_Term[]|WP_Error $terms    Array of attached terms, or WP_Error on failure.	 * @param int                $post_id  Post ID.	 * @param string             $taxonomy Name of the taxonomy.	 */	$terms = apply_filters( 'get_the_terms', $terms, $post->ID, $taxonomy ); 	if ( empty( $terms ) ) {		return false;	} 	return $terms;}

Changelog

Introduced in 2.5.0. 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 6.8.8 tag, from src/wp-includes/category-template.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.
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