Some implementation notes:
Support was added for MYSQL_TYPE_GEOMETRY to the MySQLi extension in PHP 5.3.
Note there are different internal implementations within libmysql and mysqlnd for handling columns of type MYSQL_TYPE_GEOMETRY. Generally speaking, mysqlnd will allocate significantly less memory. For example, if there is a POINT column in a result set, libmysql may pre-allocate up to 4GB of RAM although less than 50 bytes are needed for holding a POINT column in memory. Memory allocation is much lower, less than 50 bytes, if using mysqlnd.