I am currently using the following query to get some numbers:
SELECT gid, count(gid), (SELECT cou FROM size WHERE gid = infor.gid)
FROM infor
WHERE id==4325
GROUP BY gid;
The output I am getting at my current stage is the following:
+----------+-----------------+---------------------------------------------------------------+
| gid | count(gid) | (SELECT gid FROM size WHERE gid=infor.gid) |
+----------+-----------------+---------------------------------------------------------------+
| 19 | 1 | 19 |
| 27 | 4 | 27 |
| 556 | 1 | 556 |
+----------+-----------------+---------------------------------------------------------------+
I am trying to calculate the weighted average i.e.
(1*19+4*27+1*556)/(19+27+556)
Is there a way to do this using a single query?