# 1905 UNION Operator Sometimes Causes IDE Duplicate Key Exception

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During debugging program in Delphi IDE if query with UNION operator is executed and there are duplicates on each duplicate exception dialog with message like "Duplication value on index "Merge"' is raised. It is annonying and only way to suppress this dialog - to suppress EDBISAMEngineError by means of "Tools/Debugger Options/Languages Exceptions" dialog is not very viable as "real" (i.e. from my own code) DBISAM exceptions will be suppressed.