I am trying to write a query that selects from both a correlated subquery and a table in the main query, and I'm having a lot of trouble getting the proper row count. I'm sure this is very simple, and I'm just missing it. I'll try and present a simple example. For this example, there are 27 rows, organized like this:
mysql> select count(*), target_name_id, ep, wafer_id from data_cst where target_name_id = 44 group by target_name_id, ep, wafer_id; +----------+----------------+------+----------+ | count(*) | target_name_id | ep | wafer_id | +----------+----------------+------+----------+ | 6 | 44 | 1,1 | 16 | | 3 | 44 | 1,1 | 17 | | 6 | 44 | 1,2 | 16 | | 3 | 44 | 1,2 | 17 | | 6 | 44 | 1,3 | 16 | | 3 | 44 | 1,3 | 17 | +----------+----------------+------+----------+ 6 rows in set (0.00 sec) I need to get an average of a column grouped by target_name_id, ep as well as the average of the averages grouped by target_name_id, ep, wafer_id, and I also need the count of the rows in the target_name_id, ep group. My query is getting the correct averages, but incorrect row counts: mysql> select count(*), target_name_id, ep, avg(bottom), avg(averages) from (select avg(bottom) as averages, target_name_id as t, ep as e from data_cst where target_name_id = 44 group by target_name_id, ep, wafer_id) x, data_cst where target_name_id = t and ep = e group by target_name_id, ep; +----------+----------------+------+-------------+-----------------+ | count(*) | target_name_id | ep | avg(bottom) | avg(averages) | +----------+----------------+------+-------------+-----------------+ | 18 | 44 | 1,1 | 21.8056667 | 21.85458330000 | | 18 | 44 | 1,2 | 121.7984444 | 121.83983335000 | | 18 | 44 | 1,3 | 349.7634444 | 349.75016665000 | +----------+----------------+------+-------------+-----------------+ 3 rows in set (0.01 sec) The count for each row should be 9. What do I need in my count() to be counting the right thing? TIA! -larry -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql
