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posts_groupby_request хук-фильтр . WP 2.5.0

Filters the GROUP BY clause of the query.

For use by caching plugins.

Использование

add_filter( 'posts_groupby_request', 'filter_function_name_6532', 10, 2 );
function filter_function_name_6532( $groupby, $this ){
	// filter...

	return $groupby;
}
$groupby(строка)
The GROUP BY clause of the query.
$this(WP_Query)
The WP_Query instance (passed by reference).

Где используется хук

WP_Query::get_posts() остальные хуки:

Код хука

Фрагмент из: wp-includes/class-wp-query.php VER 4.9.7
...
			 * @param string   $where The WHERE clause of the query.
			 * @param WP_Query $this The WP_Query instance (passed by reference).
			 */
			$where = apply_filters_ref_array( 'posts_where_request', array( $where, &$this ) );

			/**
			 * Filters the GROUP BY clause of the query.
			 *
			 * For use by caching plugins.
			 *
			 * @since 2.5.0
			 *
			 * @param string   $groupby The GROUP BY clause of the query.
			 * @param WP_Query $this    The WP_Query instance (passed by reference).
			 */
			$groupby = apply_filters_ref_array( 'posts_groupby_request', array( $groupby, &$this ) );

			/**
			 * Filters the JOIN clause of the query.
			 *
			 * For use by caching plugins.
			 *
			 * @since 2.5.0
			 *
			 * @param string   $join  The JOIN clause of the query.
			 * @param WP_Query $this The WP_Query instance (passed by reference).
			 */
			$join = apply_filters_ref_array( 'posts_join_request', array( $join, &$this ) );

			/**
			 * Filters the ORDER BY clause of the query.
...