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filter is not described

posts_clauses filter-hook . WP 3.1.0

Filters all query clauses at once, for convenience.

Covers the WHERE, GROUP BY, JOIN, ORDER BY, DISTINCT, fields (SELECT), and LIMITS clauses.

Usage

add_filter( 'posts_clauses', 'filter_function_name_1930', 10, 2 );
function filter_function_name_1930( $clauses, $this ){
	// filter...

	return $clauses;
}
$clauses(array)
The list of clauses for the query.
$this(WP_Query)
The WP_Query instance (passed by reference).

Where the hook is called

WP_Query::get_posts()
posts_clauses
wp-includes/class-wp-query.php 2582
$clauses = (array) apply_filters_ref_array( 'posts_clauses', array( compact( $pieces ), &$this ) );

Where the hook is used (in WP core)

wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php 51
add_filter( 'posts_clauses', '_filter_query_attachment_filenames' );
wp-includes/post.php 6546
remove_filter( 'posts_clauses', __FUNCTION__ );
wp-admin/includes/ajax-actions.php 2470
add_filter( 'posts_clauses', '_filter_query_attachment_filenames' );
wp-admin/includes/post.php 1177
add_filter( 'posts_clauses', '_filter_query_attachment_filenames' );