term_exists( int|string $term, string $taxonomy = '', int $parent = null )

Determines whether a taxonomy term exists.


Description Description

Formerly is_term(), introduced in 2.3.0.

For more information on this and similar theme functions, check out the Conditional Tags article in the Theme Developer Handbook.


Top ↑

Parameters Parameters

$term

(int|string) (Required) The term to check. Accepts term ID, slug, or name.

$taxonomy

(string) (Optional) The taxonomy name to use.

Default value: ''

$parent

(int) (Optional) ID of parent term under which to confine the exists search.

Default value: null


Top ↑

Return Return

(mixed) Returns null if the term does not exist. Returns the term ID if no taxonomy is specified and the term ID exists. Returns an array of the term ID and the term taxonomy ID if the taxonomy is specified and the pairing exists. Returns 0 if term ID 0 is passed to the function.



Top ↑

Source Source

File: wp-includes/taxonomy.php

function term_exists( $term, $taxonomy = '', $parent = null ) {
	global $wpdb;

	$select     = "SELECT term_id FROM $wpdb->terms as t WHERE ";
	$tax_select = "SELECT tt.term_id, tt.term_taxonomy_id FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy as tt ON tt.term_id = t.term_id WHERE ";

	if ( is_int( $term ) ) {
		if ( 0 === $term ) {
			return 0;
		}
		$where = 't.term_id = %d';
		if ( ! empty( $taxonomy ) ) {
			// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.ReplacementsWrongNumber
			return $wpdb->get_row( $wpdb->prepare( $tax_select . $where . ' AND tt.taxonomy = %s', $term, $taxonomy ), ARRAY_A );
		} else {
			return $wpdb->get_var( $wpdb->prepare( $select . $where, $term ) );
		}
	}

	$term = trim( wp_unslash( $term ) );
	$slug = sanitize_title( $term );

	$where             = 't.slug = %s';
	$else_where        = 't.name = %s';
	$where_fields      = array( $slug );
	$else_where_fields = array( $term );
	$orderby           = 'ORDER BY t.term_id ASC';
	$limit             = 'LIMIT 1';
	if ( ! empty( $taxonomy ) ) {
		if ( is_numeric( $parent ) ) {
			$parent              = (int) $parent;
			$where_fields[]      = $parent;
			$else_where_fields[] = $parent;
			$where              .= ' AND tt.parent = %d';
			$else_where         .= ' AND tt.parent = %d';
		}

		$where_fields[]      = $taxonomy;
		$else_where_fields[] = $taxonomy;

		$result = $wpdb->get_row( $wpdb->prepare( "SELECT tt.term_id, tt.term_taxonomy_id FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy as tt ON tt.term_id = t.term_id WHERE $where AND tt.taxonomy = %s $orderby $limit", $where_fields ), ARRAY_A );
		if ( $result ) {
			return $result;
		}

		return $wpdb->get_row( $wpdb->prepare( "SELECT tt.term_id, tt.term_taxonomy_id FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy as tt ON tt.term_id = t.term_id WHERE $else_where AND tt.taxonomy = %s $orderby $limit", $else_where_fields ), ARRAY_A );
	}

	// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.UnfinishedPrepare
	$result = $wpdb->get_var( $wpdb->prepare( "SELECT term_id FROM $wpdb->terms as t WHERE $where $orderby $limit", $where_fields ) );
	if ( $result ) {
		return $result;
	}

	// phpcs:ignore WordPress.DB.PreparedSQLPlaceholders.UnfinishedPrepare
	return $wpdb->get_var( $wpdb->prepare( "SELECT term_id FROM $wpdb->terms as t WHERE $else_where $orderby $limit", $else_where_fields ) );
}

Top ↑

Changelog Changelog

Changelog
Version Description
3.0.0 Introduced.

Top ↑

User Contributed Notes User Contributed Notes

  1. Skip to note 2 content
    Contributed by Codex

    Checks to see if ‘Uncategorized’ category exists
    Check if the ‘Uncategorized’ category exists
    Note: term_exists() runs a database query. get_term() can be used for the same purpose, except it uses the term cache.

    $term = term_exists( 'Uncategorized', 'category' );
    if ( $term !== 0 && $term !== null ) {
    	echo __( "'Uncategorized' category exists!", "textdomain" );
    }
    
  2. Skip to note 3 content
    Contributed by Codex

    Checks to see if ‘Untagged’ post_tag category exists
    Note: term_exists() runs a database query. get_term() can be used for the same purpose, except it uses the term cache.

    $term = term_exists( 'Untagged', 'post_tag' );
    if ( $term !== 0 && $term !== null ) {
    	echo __( "'Untagged' post_tag exists!", "textdomain" );
    }
    

You must log in before being able to contribute a note or feedback.