There is not enough main memory available to open a database session. The maximum main memory available is determined by the special database parameter CAT_CACHE_SUPPLY when installing the database instance.

The amount of main memory available is not sufficient to execute the required database procedure.

You can only open a session when at least one other user has terminated their session. Check whether the value of the database parameter CAT_CACHE_SUPPLY is sufficient.

Try to execute the database procedure at a later stage.