Question

I have the following query which returns the following error:
An aggregate may not appear in the WHERE clause unless it is in a subquery contained in a HAVING clause or a select list, and the column being aggregated is an outer reference.

SELECT Part from Parts Where count(Part) > 1

How could i rewrite it to return the part that appears more than once.

Answer 1

You need to use a GROUP BY and HAVING clause like this:

SELECT part
FROM Parts
GROUP BY part
HAVING COUNT(*) > 1