Before proceeding to create tables, you should create a DBEFile and add it to the SYSTEM DBEFileSet to provide additional space for sort operations and for expansion of the DBEnvironment. Use the following statements:
   isql=> CREATE DBEFILE DBEFile1 Return
   > WITH PAGES=50, Return
   > NAME = 'DBEFILE1', TYPE = MIXED; Return
   isql=> ADD DBEFILE DBEFile1 Return
   > TO DBEFILESET SYSTEM; Return
   isql=> COMMIT WORK; Return
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You can use this procedure with different DBEFile names any time you want to add space to the SYSTEM DBEFileSet.