-915: No more memory 

Explanation:

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       1.      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.

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

User Action:

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       1.      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.

       2.      Try to execute the database procedure at a later stage.