Error "ORA-00918: column ambiguously defined" Occurs when Tables in a Join are Renamed Similarly
Published: 07 Apr 2022 Last Modified Date: 08 Jul 2022
Issue
Error "ORA-00918: column ambiguously defined" occurs when 2 tables with similar names are joined as shown below.
Environment
Tableau Desktop
Oracle
Resolution
Workaround
Use different table names less than 30 characters long
Cause
This is due to the Oracle (12.1 and earlier) design limitation on object name length. Part of the table names that are longer than 30 characters are truncated and end up as being ambiguous.
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