get_metadata_raw()WP 5.5.0

Retrieves raw metadata value for the specified object.

Return

Mixed. An array of values if $single is false. The value of the meta field if $single is true. False for an invalid $object_id (non-numeric, zero, or negative value), or if $meta_type is not specified. Null if the value does not exist.

Usage

get_metadata_raw( $meta_type, $object_id, $meta_key, $single );
$meta_type(string) (required)
Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user', or any other object type with an associated meta table.
$object_id(int) (required)
ID of the object metadata is for.
$meta_key(string)
Metadata key. If not specified, retrieve all metadata for the specified object.
Default: empty string
$single(true|false)
If true, return only the first value of the specified $meta_key. This parameter has no effect if $meta_key is not specified.
Default: false

Changelog

Since 5.5.0 Introduced.

get_metadata_raw() code WP 6.6.2

function get_metadata_raw( $meta_type, $object_id, $meta_key = '', $single = false ) {
	if ( ! $meta_type || ! is_numeric( $object_id ) ) {
		return false;
	}

	$object_id = absint( $object_id );
	if ( ! $object_id ) {
		return false;
	}

	/**
	 * Short-circuits the return value of a meta field.
	 *
	 * The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
	 * (post, comment, term, user, or any other type with an associated meta table).
	 * Returning a non-null value will effectively short-circuit the function.
	 *
	 * Possible filter names include:
	 *
	 *  - `get_post_metadata`
	 *  - `get_comment_metadata`
	 *  - `get_term_metadata`
	 *  - `get_user_metadata`
	 *
	 * @since 3.1.0
	 * @since 5.5.0 Added the `$meta_type` parameter.
	 *
	 * @param mixed  $value     The value to return, either a single metadata value or an array
	 *                          of values depending on the value of `$single`. Default null.
	 * @param int    $object_id ID of the object metadata is for.
	 * @param string $meta_key  Metadata key.
	 * @param bool   $single    Whether to return only the first value of the specified `$meta_key`.
	 * @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
	 *                          or any other object type with an associated meta table.
	 */
	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, $single, $meta_type );
	if ( null !== $check ) {
		if ( $single && is_array( $check ) ) {
			return $check[0];
		} else {
			return $check;
		}
	}

	$meta_cache = wp_cache_get( $object_id, $meta_type . '_meta' );

	if ( ! $meta_cache ) {
		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
		if ( isset( $meta_cache[ $object_id ] ) ) {
			$meta_cache = $meta_cache[ $object_id ];
		} else {
			$meta_cache = null;
		}
	}

	if ( ! $meta_key ) {
		return $meta_cache;
	}

	if ( isset( $meta_cache[ $meta_key ] ) ) {
		if ( $single ) {
			return maybe_unserialize( $meta_cache[ $meta_key ][0] );
		} else {
			return array_map( 'maybe_unserialize', $meta_cache[ $meta_key ] );
		}
	}

	return null;
}