Error 603



Message text

There are not enough system session descriptors available to run this query. Raise the value of the configuration parameter ’number of aux scan descriptors’ or retry your query later. 


This error occurs when Adaptive Server runs out of system session descriptors when running a query. Error 603 can occur on commands which create, drop, and update objects, as these commands often have many dependencies on system tables which Adaptive Server must handle to complete the command.

Session descriptors are the data structures used to manage access to Adaptive Server objects. Session descriptors come in three forms—user session descriptors (including worktable session descriptors), system session descriptors, and worktable session descriptors.

Session descriptors are used when:

You cannot change the number of session descriptors available to a query.


When you error 603 is raised, you must simplify your query or command. To recover from this error, split up your query or simplify the command and run it again.

For example, if you are entering a drop procedure command and that procedure contains other procedures or triggers, you can simplify your command by dropping the other procedures or triggers manually before running the drop procedure command.

Additional information

Refer to the chapter “Setting Configuration Parameters” in the System Administration Guide: Volume 1 for a description of “number of aux scan descriptors” and how queries use scan descriptors.

Versions in which this error is raised

All versions