This Wiki is based on Forum Post: WCF-SQL, Table Select: The columns are either duplicated or not in a sequence


While moving a working interface from one environment to another environment (e.g. from Test environment to Production environment), WCF-SQL Adapter started throwing the following error in the new environment:

The columns abc and xyz are either duplicated or not in a sequence. Each column can only be selected one time, and columns must be selected in sequence.

Root Cause

Root cause of this issue is using Select * in polling statement while generating the Polling Schema and then in polling statement on Receive Location, and column sequence is different in both environments:


Solution is to use specific columns (better to use aliases) in polling statements:

See Also

Read suggested related topics:

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