Violation of … constraint ‘…’. Cannot insert duplicate key in object ‘…’ (Msg 2627)

Transact-SQL
1

Hi, I am getting the error message

Violation of … constraint ‘…’. Cannot insert duplicate key in object ‘…’ (Msg 2627)

when I try to insert records into a table using MERGE command.

Actually, the target table which I try to insert records is empty & does not have any records now.

Please tell me why I am getting this error message as no existing records are there, there by preventing duplicate insertion.

2

The source data itself must have the duplicates. Find out why

1 Like
3

Either the source data has duplicates - or the MERGE is causing the same row to be inserted/updated multiple times. This can be caused by an invalid join criteria or missing criteria.

4

Just run the source query and see where there might be duplicates

5

Thanks for the insight. The source query was returning duplicate records. I will use DISTINCT clause & see the output.