Retrieves the query results.
Description
The return type varies depending on the value passed to $args['fields'].
The following will result in an array of WP_Term objects being returned:
- ‘all’
- ‘all_with_object_id’
The following will result in a numeric string being returned:
- ‘count’
The following will result in an array of text strings being returned:
- ‘id=>name’
- ‘id=>slug’
- ‘names’
- ‘slugs’
The following will result in an array of numeric strings being returned:
- ‘id=>parent’
The following will result in an array of integers being returned:
- ‘ids’
- ‘tt_ids’
Source
public function get_terms() {
global $wpdb;
$this->parse_query( $this->query_vars );
$args = &$this->query_vars;
// Set up meta_query so it's available to 'pre_get_terms'.
$this->meta_query = new WP_Meta_Query();
$this->meta_query->parse_query_vars( $args );
/**
* Fires before terms are retrieved.
*
* @since 4.6.0
*
* @param WP_Term_Query $query Current instance of WP_Term_Query (passed by reference).
*/
do_action_ref_array( 'pre_get_terms', array( &$this ) );
$taxonomies = (array) $args['taxonomy'];
// Save queries by not crawling the tree in the case of multiple taxes or a flat tax.
$has_hierarchical_tax = false;
if ( $taxonomies ) {
foreach ( $taxonomies as $_tax ) {
if ( is_taxonomy_hierarchical( $_tax ) ) {
$has_hierarchical_tax = true;
}
}
} else {
// When no taxonomies are provided, assume we have to descend the tree.
$has_hierarchical_tax = true;
}
if ( ! $has_hierarchical_tax ) {
$args['hierarchical'] = false;
$args['pad_counts'] = false;
}
// 'parent' overrides 'child_of'.
if ( 0 < (int) $args['parent'] ) {
$args['child_of'] = false;
}
if ( 'all' === $args['get'] ) {
$args['childless'] = false;
$args['child_of'] = 0;
$args['hide_empty'] = 0;
$args['hierarchical'] = false;
$args['pad_counts'] = false;
}
/**
* Filters the terms query arguments.
*
* @since 3.1.0
*
* @param array $args An array of get_terms() arguments.
* @param string[] $taxonomies An array of taxonomy names.
*/
$args = apply_filters( 'get_terms_args', $args, $taxonomies );
// Avoid the query if the queried parent/child_of term has no descendants.
$child_of = $args['child_of'];
$parent = $args['parent'];
if ( $child_of ) {
$_parent = $child_of;
} elseif ( $parent ) {
$_parent = $parent;
} else {
$_parent = false;
}
if ( $_parent ) {
$in_hierarchy = false;
foreach ( $taxonomies as $_tax ) {
$hierarchy = _get_term_hierarchy( $_tax );
if ( isset( $hierarchy[ $_parent ] ) ) {
$in_hierarchy = true;
}
}
if ( ! $in_hierarchy ) {
if ( 'count' === $args['fields'] ) {
return 0;
} else {
$this->terms = array();
return $this->terms;
}
}
}
// 'term_order' is a legal sort order only when joining the relationship table.
$_orderby = $this->query_vars['orderby'];
if ( 'term_order' === $_orderby && empty( $this->query_vars['object_ids'] ) ) {
$_orderby = 'term_id';
}
$orderby = $this->parse_orderby( $_orderby );
if ( $orderby ) {
$orderby = "ORDER BY $orderby";
}
$order = $this->parse_order( $this->query_vars['order'] );
if ( $taxonomies ) {
$this->sql_clauses['where']['taxonomy'] =
"tt.taxonomy IN ('" . implode( "', '", array_map( 'esc_sql', $taxonomies ) ) . "')";
}
if ( empty( $args['exclude'] ) ) {
$args['exclude'] = array();
}
if ( empty( $args['include'] ) ) {
$args['include'] = array();
}
$exclude = $args['exclude'];
$exclude_tree = $args['exclude_tree'];
$include = $args['include'];
$inclusions = '';
if ( ! empty( $include ) ) {
$exclude = '';
$exclude_tree = '';
$inclusions = implode( ',', wp_parse_id_list( $include ) );
}
if ( ! empty( $inclusions ) ) {
$this->sql_clauses['where']['inclusions'] = 't.term_id IN ( ' . $inclusions . ' )';
}
$exclusions = array();
if ( ! empty( $exclude_tree ) ) {
$exclude_tree = wp_parse_id_list( $exclude_tree );
$excluded_children = $exclude_tree;
foreach ( $exclude_tree as $extrunk ) {
$excluded_children = array_merge(
$excluded_children,
(array) get_terms(
array(
'taxonomy' => reset( $taxonomies ),
'child_of' => (int) $extrunk,
'fields' => 'ids',
'hide_empty' => 0,
)
)
);
}
$exclusions = array_merge( $excluded_children, $exclusions );
}
if ( ! empty( $exclude ) ) {
$exclusions = array_merge( wp_parse_id_list( $exclude ), $exclusions );
}
// 'childless' terms are those without an entry in the flattened term hierarchy.
$childless = (bool) $args['childless'];
if ( $childless ) {
foreach ( $taxonomies as $_tax ) {
$term_hierarchy = _get_term_hierarchy( $_tax );
$exclusions = array_merge( array_keys( $term_hierarchy ), $exclusions );
}
}
if ( ! empty( $exclusions ) ) {
$exclusions = 't.term_id NOT IN (' . implode( ',', array_map( 'intval', $exclusions ) ) . ')';
} else {
$exclusions = '';
}
/**
* Filters the terms to exclude from the terms query.
*
* @since 2.3.0
*
* @param string $exclusions `NOT IN` clause of the terms query.
* @param array $args An array of terms query arguments.
* @param string[] $taxonomies An array of taxonomy names.
*/
$exclusions = apply_filters( 'list_terms_exclusions', $exclusions, $args, $taxonomies );
if ( ! empty( $exclusions ) ) {
// Strip leading 'AND'. Must do string manipulation here for backward compatibility with filter.
$this->sql_clauses['where']['exclusions'] = preg_replace( '/^\s*AND\s*/', '', $exclusions );
}
if ( '' === $args['name'] ) {
$args['name'] = array();
} else {
$args['name'] = (array) $args['name'];
}
if ( ! empty( $args['name'] ) ) {
$names = $args['name'];
foreach ( $names as &$_name ) {
// `sanitize_term_field()` returns slashed data.
$_name = stripslashes( sanitize_term_field( 'name', $_name, 0, reset( $taxonomies ), 'db' ) );
}
$this->sql_clauses['where']['name'] = "t.name IN ('" . implode( "', '", array_map( 'esc_sql', $names ) ) . "')";
}
if ( '' === $args['slug'] ) {
$args['slug'] = array();
} else {
$args['slug'] = array_map( 'sanitize_title', (array) $args['slug'] );
}
if ( ! empty( $args['slug'] ) ) {
$slug = implode( "', '", $args['slug'] );
$this->sql_clauses['where']['slug'] = "t.slug IN ('" . $slug . "')";
}
if ( '' === $args['term_taxonomy_id'] ) {
$args['term_taxonomy_id'] = array();
} else {
$args['term_taxonomy_id'] = array_map( 'intval', (array) $args['term_taxonomy_id'] );
}
if ( ! empty( $args['term_taxonomy_id'] ) ) {
$tt_ids = implode( ',', $args['term_taxonomy_id'] );
$this->sql_clauses['where']['term_taxonomy_id'] = "tt.term_taxonomy_id IN ({$tt_ids})";
}
if ( ! empty( $args['name__like'] ) ) {
$this->sql_clauses['where']['name__like'] = $wpdb->prepare(
't.name LIKE %s',
'%' . $wpdb->esc_like( $args['name__like'] ) . '%'
);
}
if ( ! empty( $args['description__like'] ) ) {
$this->sql_clauses['where']['description__like'] = $wpdb->prepare(
'tt.description LIKE %s',
'%' . $wpdb->esc_like( $args['description__like'] ) . '%'
);
}
if ( '' === $args['object_ids'] ) {
$args['object_ids'] = array();
} else {
$args['object_ids'] = array_map( 'intval', (array) $args['object_ids'] );
}
if ( ! empty( $args['object_ids'] ) ) {
$object_ids = implode( ', ', $args['object_ids'] );
$this->sql_clauses['where']['object_ids'] = "tr.object_id IN ($object_ids)";
}
/*
* When querying for object relationships, the 'count > 0' check
* added by 'hide_empty' is superfluous.
*/
if ( ! empty( $args['object_ids'] ) ) {
$args['hide_empty'] = false;
}
if ( '' !== $parent ) {
$parent = (int) $parent;
$this->sql_clauses['where']['parent'] = "tt.parent = '$parent'";
}
$hierarchical = $args['hierarchical'];
if ( 'count' === $args['fields'] ) {
$hierarchical = false;
}
if ( $args['hide_empty'] && ! $hierarchical ) {
$this->sql_clauses['where']['count'] = 'tt.count > 0';
}
$number = $args['number'];
$offset = $args['offset'];
// Don't limit the query results when we have to descend the family tree.
if ( $number && ! $hierarchical && ! $child_of && '' === $parent ) {
if ( $offset ) {
$limits = 'LIMIT ' . $offset . ',' . $number;
} else {
$limits = 'LIMIT ' . $number;
}
} else {
$limits = '';
}
if ( ! empty( $args['search'] ) ) {
$this->sql_clauses['where']['search'] = $this->get_search_sql( $args['search'] );
}
// Meta query support.
$join = '';
$distinct = '';
// Reparse meta_query query_vars, in case they were modified in a 'pre_get_terms' callback.
$this->meta_query->parse_query_vars( $this->query_vars );
$mq_sql = $this->meta_query->get_sql( 'term', 't', 'term_id' );
$meta_clauses = $this->meta_query->get_clauses();
if ( ! empty( $meta_clauses ) ) {
$join .= $mq_sql['join'];
// Strip leading 'AND'.
$this->sql_clauses['where']['meta_query'] = preg_replace( '/^\s*AND\s*/', '', $mq_sql['where'] );
$distinct .= 'DISTINCT';
}
$selects = array();
switch ( $args['fields'] ) {
case 'count':
$orderby = '';
$order = '';
$selects = array( 'COUNT(*)' );
break;
default:
$selects = array( 't.term_id' );
if ( 'all_with_object_id' === $args['fields'] && ! empty( $args['object_ids'] ) ) {
$selects[] = 'tr.object_id';
}
break;
}
$_fields = $args['fields'];
/**
* Filters the fields to select in the terms query.
*
* Field lists modified using this filter will only modify the term fields returned
* by the function when the `$fields` parameter set to 'count' or 'all'. In all other
* cases, the term fields in the results array will be determined by the `$fields`
* parameter alone.
*
* Use of this filter can result in unpredictable behavior, and is not recommended.
*
* @since 2.8.0
*
* @param string[] $selects An array of fields to select for the terms query.
* @param array $args An array of term query arguments.
* @param string[] $taxonomies An array of taxonomy names.
*/
$fields = implode( ', ', apply_filters( 'get_terms_fields', $selects, $args, $taxonomies ) );
$join .= " INNER JOIN $wpdb->term_taxonomy AS tt ON t.term_id = tt.term_id";
if ( ! empty( $this->query_vars['object_ids'] ) ) {
$join .= " INNER JOIN {$wpdb->term_relationships} AS tr ON tr.term_taxonomy_id = tt.term_taxonomy_id";
$distinct = 'DISTINCT';
}
$where = implode( ' AND ', $this->sql_clauses['where'] );
$pieces = array( 'fields', 'join', 'where', 'distinct', 'orderby', 'order', 'limits' );
/**
* Filters the terms query SQL clauses.
*
* @since 3.1.0
*
* @param string[] $clauses {
* Associative array of the clauses for the query.
*
* @type string $fields The SELECT clause of the query.
* @type string $join The JOIN clause of the query.
* @type string $where The WHERE clause of the query.
* @type string $distinct The DISTINCT clause of the query.
* @type string $orderby The ORDER BY clause of the query.
* @type string $order The ORDER clause of the query.
* @type string $limits The LIMIT clause of the query.
* }
* @param string[] $taxonomies An array of taxonomy names.
* @param array $args An array of term query arguments.
*/
$clauses = apply_filters( 'terms_clauses', compact( $pieces ), $taxonomies, $args );
$fields = isset( $clauses['fields'] ) ? $clauses['fields'] : '';
$join = isset( $clauses['join'] ) ? $clauses['join'] : '';
$where = isset( $clauses['where'] ) ? $clauses['where'] : '';
$distinct = isset( $clauses['distinct'] ) ? $clauses['distinct'] : '';
$orderby = isset( $clauses['orderby'] ) ? $clauses['orderby'] : '';
$order = isset( $clauses['order'] ) ? $clauses['order'] : '';
$limits = isset( $clauses['limits'] ) ? $clauses['limits'] : '';
$fields_is_filtered = implode( ', ', $selects ) !== $fields;
if ( $where ) {
$where = "WHERE $where";
}
$this->sql_clauses['select'] = "SELECT $distinct $fields";
$this->sql_clauses['from'] = "FROM $wpdb->terms AS t $join";
$this->sql_clauses['orderby'] = $orderby ? "$orderby $order" : '';
$this->sql_clauses['limits'] = $limits;
// Beginning of the string is on a new line to prevent leading whitespace. See https://core.trac.wordpress.org/ticket/56841.
$this->request =
"{$this->sql_clauses['select']}
{$this->sql_clauses['from']}
{$where}
{$this->sql_clauses['orderby']}
{$this->sql_clauses['limits']}";
$this->terms = null;
/**
* Filters the terms array before the query takes place.
*
* Return a non-null value to bypass WordPress' default term queries.
*
* @since 5.3.0
*
* @param array|null $terms Return an array of term data to short-circuit WP's term query,
* or null to allow WP queries to run normally.
* @param WP_Term_Query $query The WP_Term_Query instance, passed by reference.
*/
$this->terms = apply_filters_ref_array( 'terms_pre_query', array( $this->terms, &$this ) );
if ( null !== $this->terms ) {
return $this->terms;
}
if ( $args['cache_results'] ) {
$cache_key = $this->generate_cache_key( $args, $this->request );
$cache = wp_cache_get( $cache_key, 'term-queries' );
if ( false !== $cache ) {
if ( 'ids' === $_fields ) {
$cache = array_map( 'intval', $cache );
} elseif ( 'count' !== $_fields ) {
if ( ( 'all_with_object_id' === $_fields && ! empty( $args['object_ids'] ) )
|| ( 'all' === $_fields && $args['pad_counts'] || $fields_is_filtered )
) {
$term_ids = wp_list_pluck( $cache, 'term_id' );
} else {
$term_ids = array_map( 'intval', $cache );
}
_prime_term_caches( $term_ids, $args['update_term_meta_cache'] );
$term_objects = $this->populate_terms( $cache );
$cache = $this->format_terms( $term_objects, $_fields );
}
$this->terms = $cache;
return $this->terms;
}
}
if ( 'count' === $_fields ) {
$count = $wpdb->get_var( $this->request ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
if ( $args['cache_results'] ) {
wp_cache_set( $cache_key, $count, 'term-queries' );
}
return $count;
}
$terms = $wpdb->get_results( $this->request ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
if ( empty( $terms ) ) {
if ( $args['cache_results'] ) {
wp_cache_add( $cache_key, array(), 'term-queries' );
}
return array();
}
$term_ids = wp_list_pluck( $terms, 'term_id' );
_prime_term_caches( $term_ids, false );
$term_objects = $this->populate_terms( $terms );
if ( $child_of ) {
foreach ( $taxonomies as $_tax ) {
$children = _get_term_hierarchy( $_tax );
if ( ! empty( $children ) ) {
$term_objects = _get_term_children( $child_of, $term_objects, $_tax );
}
}
}
// Update term counts to include children.
if ( $args['pad_counts'] && 'all' === $_fields ) {
foreach ( $taxonomies as $_tax ) {
_pad_term_counts( $term_objects, $_tax );
}
}
// Make sure we show empty categories that have children.
if ( $hierarchical && $args['hide_empty'] && is_array( $term_objects ) ) {
foreach ( $term_objects as $k => $term ) {
if ( ! $term->count ) {
$children = get_term_children( $term->term_id, $term->taxonomy );
if ( is_array( $children ) ) {
foreach ( $children as $child_id ) {
$child = get_term( $child_id, $term->taxonomy );
if ( $child->count ) {
continue 2;
}
}
}
// It really is empty.
unset( $term_objects[ $k ] );
}
}
}
// Hierarchical queries are not limited, so 'offset' and 'number' must be handled now.
if ( $hierarchical && $number && is_array( $term_objects ) ) {
if ( $offset >= count( $term_objects ) ) {
$term_objects = array();
} else {
$term_objects = array_slice( $term_objects, $offset, $number, true );
}
}
// Prime termmeta cache.
if ( $args['update_term_meta_cache'] ) {
$term_ids = wp_list_pluck( $term_objects, 'term_id' );
wp_lazyload_term_meta( $term_ids );
}
if ( 'all_with_object_id' === $_fields && ! empty( $args['object_ids'] ) ) {
$term_cache = array();
foreach ( $term_objects as $term ) {
$object = new stdClass();
$object->term_id = $term->term_id;
$object->object_id = $term->object_id;
$term_cache[] = $object;
}
} elseif ( 'all' === $_fields && $args['pad_counts'] ) {
$term_cache = array();
foreach ( $term_objects as $term ) {
$object = new stdClass();
$object->term_id = $term->term_id;
$object->count = $term->count;
$term_cache[] = $object;
}
} elseif ( $fields_is_filtered ) {
$term_cache = $term_objects;
} else {
$term_cache = wp_list_pluck( $term_objects, 'term_id' );
}
if ( $args['cache_results'] ) {
wp_cache_add( $cache_key, $term_cache, 'term-queries' );
}
$this->terms = $this->format_terms( $term_objects, $_fields );
return $this->terms;
}
Hooks
- apply_filters( ‘get_terms_args’,
array $args ,string[] $taxonomies ) Filters the terms query arguments.
- apply_filters( ‘get_terms_fields’,
string[] $selects ,array $args ,string[] $taxonomies ) Filters the fields to select in the terms query.
- apply_filters( ‘list_terms_exclusions’,
string $exclusions ,array $args ,string[] $taxonomies ) Filters the terms to exclude from the terms query.
- do_action_ref_array( ‘pre_get_terms’,
WP_Term_Query $query ) Fires before terms are retrieved.
- apply_filters( ‘terms_clauses’,
string[] $clauses ,string[] $taxonomies ,array $args ) Filters the terms query SQL clauses.
- apply_filters_ref_array( ‘terms_pre_query’,
array|null $terms ,WP_Term_Query $query ) Filters the terms array before the query takes place.
Changelog
| Version | Description |
|---|---|
| 4.6.0 | Introduced. |
User Contributed Notes