I have a query. The task was "Return customers from Spain who did not place orders". But my mendor says about this query:
"your query can potentially return incorrect results, please figure out the conditions when it can be possible and fix it"
What soes it mean?
SELECT custid, companyname,country
WHERE country = 'Spain'
AND custid NOT IN (SELECT custid FROM [TestSQL].[Sales].[Orders])
View Complete Post