Retrieves metadata by meta ID.

$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.

$meta_id int Required

ID for a specific meta row.

stdClass|false Metadata object, or boolean false if the metadata doesn't exist.

• meta_keystring
  The meta key.
• meta_valuemixed
  The unserialized meta value.
• meta_idstring
  Optional. The meta ID when the meta type is any value except 'user'.
• umeta_idstring
  Optional. The meta ID when the meta type is 'user'.
• post_idstring
  Optional. The object ID when the meta type is 'post'.
• comment_idstring
  Optional. The object ID when the meta type is 'comment'.
• term_idstring
  Optional. The object ID when the meta type is 'term'.
• user_idstring
  Optional. The object ID when the meta type is 'user'.

File: wp-includes/meta.php. View all references

function get_metadata_by_mid( $meta_type, $meta_id ) {
	global $wpdb;

	if ( ! $meta_type || ! is_numeric( $meta_id ) || floor( $meta_id ) != $meta_id ) {
		return false;
	}

	$meta_id = (int) $meta_id;
	if ( $meta_id <= 0 ) {
		return false;
	}

	$table = _get_meta_table( $meta_type );
	if ( ! $table ) {
		return false;
	}

	/**
	 * Short-circuits the return value when fetching a meta field by meta ID.
	 *
	 * 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 hook names include:
	 *
	 *  - `get_post_metadata_by_mid`
	 *  - `get_comment_metadata_by_mid`
	 *  - `get_term_metadata_by_mid`
	 *  - `get_user_metadata_by_mid`
	 *
	 * @since 5.0.0
	 *
	 * @param stdClass|null $value   The value to return.
	 * @param int           $meta_id Meta ID.
	 */
	$check = apply_filters( "get_{$meta_type}_metadata_by_mid", null, $meta_id );
	if ( null !== $check ) {
		return $check;
	}

	$id_column = ( 'user' === $meta_type ) ? 'umeta_id' : 'meta_id';

	$meta = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $table WHERE $id_column = %d", $meta_id ) );

	if ( empty( $meta ) ) {
		return false;
	}

	if ( isset( $meta->meta_value ) ) {
		$meta->meta_value = maybe_unserialize( $meta->meta_value );
	}

	return $meta;
}