计数一个串联的字段

Question

The following query is an attempt to find multiple occurrences of a concatenated field:

SELECT ID, NUM1, NUM2, CONCAT(NUM1, NUM2)
FROM TABLE
GROUP BY ID, NUM1, NUM2, CONCAT(NUM1, NUM2)
HAVING COUNT(CONCAT(NUM1, NUM2) > 1

I am currently getting a list of records with COUNT(NUM1) > 1. How can I successfully query the count of a concatenated field?

Answer 1

I ended up creating two instances of TABLE, linked by NUM1 and NUM2 separately, and inserted a ID_A != ID_B row. Not quite what I was looking for, but it works.