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filter is not described

date_query_valid_columns filter-hook . WP 3.7.0

Filters the list of valid date query columns.

Usage

add_filter( 'date_query_valid_columns', 'filter_function_name_7663' );
function filter_function_name_7663( $valid_columns ){
	// filter...

	return $valid_columns;
}
$valid_columns(string[])
An array of valid date query columns. Defaults are 'post_date', 'post_date_gmt', 'post_modified', 'post_modified_gmt', 'comment_date', 'comment_date_gmt', 'user_registered'

Changelog

Since 3.7.0 Introduced.
Since 4.1.0 Added 'user_registered' to the default recognized columns.

Where the hook is called

WP_Date_Query::validate_column()
date_query_valid_columns
wp-includes/date.php 507
if ( ! in_array( $column, apply_filters( 'date_query_valid_columns', $valid_columns ) ) ) {

Where the hook is used (in WP core)

Usage not found!