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delete_(meta_type)_metadata filter-hook . WP 3.1.0

Filters whether to delete metadata of a specific type.

The dynamic portion of the hook, $meta_type, refers to the meta object type (comment, post, term, or user). Returning a non-null value will effectively short-circuit the function.


add_filter( 'delete_(meta_type)_metadata', 'filter_function_name_6679', 10, 5 );
function filter_function_name_6679( $delete, $object_id, $meta_key, $meta_value, $delete_all ){
	// filter...

	return $delete;
Whether to allow metadata deletion of the given type.
Object ID.
Meta key.
Meta value. Must be serializable if non-scalar.
Whether to delete the matching metadata entries for all objects, ignoring the specified $object_id.
Default: false


Since 3.1.0 Introduced.

Where the hook is called

wp-includes/meta.php 370
$check = apply_filters( "delete_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $delete_all );

Where the hook is used (in WP core)

wp-includes/default-filters.php 113
add_filter( 'delete_term_metadata', 'wp_check_term_meta_support_prefilter' );
wp-includes/ms-default-filters.php 63
add_filter( 'delete_blog_metadata', 'wp_check_site_meta_support_prefilter' );