Removing duplicate rows

No need to over develop this – once you realise that the DELETE command can include the TOP option.

More? Ok. Create a SELECT command that shows the issue. EG:-

SELECT ID
FROM dbo._op2
WHERE ID = 'X123456';

Add TOP to return just the unwanted rows. IE: if the above query should return 1 row but erroneously returns 2 rows use TOP(1), if it returns 5 rows use TOP(4) …

(NOTE: It does not matter which particular rows get deleted … they are duplicates remember)

SELECT TOP(1) ID
FROM dbo._op2
WHERE ID = 'X123456';

Change SELECT to DELETE and remove the column name …

DELETE TOP(1)
FROM dbo._op2
WHERE ID = 'X123456';

… and only run it once 😉