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How To Identify the Mismatching Column Datatypes If Query Hits Ora-1790 (Doc ID 372751.1)

Last updated on FEBRUARY 03, 2022

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 8.1.7 to 11.2]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.Purpose

This Article is intended to help DBAs identify the Mismatching datatype columns when a Complex queries connected by  UNION/UNION ALL hit ORA-01790



The ORA-01790 is defined as:

Error: ORA 1790
Text: expression must have same datatype as corresponding expression
Cause: A SELECT list item corresponds to a SELECT list item with a different
datatype in another query of the same set expression.
Action: Check that all corresponding SELECT list items have the same datatypes.
Use the TO_NUMBER, TO_CHAR, and TO_DATE functions to do explicit data

Troubleshooting Steps

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Troubleshooting Steps

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