Question

So, I have next table structure :

Is there a way to make SQL query that counts simillar hashes in r_hash column, than founds this hash in hash column and returns an uid, and count of hashes?

For example – uid – 21520578; type – 1; count – 7?

Answer 1

Try the below query

SELECT T1.uid, T1.type, T2.count 
FROM table T1,
(
  SELECT r_hash, COUNT(*) AS count  
  FROM table 
  GROUP BY r_hash
) T2 
WHERE T1.hash = T2.r_hash