mysql_multi_query() executes one or more queries separated by a ; to the currently active database on the server that's associated with the specified link_identifier
function mysql_multi_query( string $query, resource $link_identifier = NULL, ): mixed;
string $query- An SQL query The query string should not end with a semicolon. Data inside the query should be properly escaped.
resource $link_identifier = NULL- The MySQL connection. If the link identifier is not specified, the last link opened by mysql_connect() is assumed. If no such link is found, it will try to create one as if mysql_connect() was called with no arguments. If no connection is found or established, an E_WARNING level error is generated.
mixed- - This is a fb specific query so behaviour is a little random at the moment.