There are three resource types used in CUBRID. The first one is the link identifier for a database connection, the second is the a resource which holds the result of a query, and the third a resource which holds the query results of BLOB/CLOB data types.
A connection identifier returned by cubrid_connect(), cubrid_connect_with_url(), cubrid_pconnect() and cubrid_pconnect_with_url().
A request identifier returned by cubrid_prepare() and cubrid_execute().
A LOB identifier returned by cubrid_lob_get().