MySQL查询-使用CAST和SUM时无效使用组函数

Question

I have the following query that's generating the "Invalid use of group function" error:

SELECT dac_name, unit_name, ptn, unit_type, monthly_recurring, directory_charges
FROM sprint WHERE date='$current_sprint_date' AND CAST( directory_charges AS DECIMAL( 10, 2 ) ) > SUM( CAST( directory_charges AS DECIMAL( 10, 2 ) ) * .01) ORDER BY CAST(directory_charges AS DECIMAL(10,2)) DESC LIMIT 10; 

Can't seem to figure it out. Any help is greatly appreciated.

Answer 1

You can't use an aggregate function like SUM() in a WHERE clause. Aggregates are dependent on the rows that are selected, so using them while selecting rows doesn't make sense. You can use it in a HAVING clause, which performs a second filter after rows have been selected and processed:

SELECT dac_name, unit_name, ptn, unit_type, monthly_recurring, directory_charges
FROM sprint
WHERE date='$current_sprint_date'
HAVING CAST( directory_charges AS DECIMAL( 10, 2 ) ) > SUM( CAST( directory_charges AS DECIMAL( 10, 2 ) ) * .01)
ORDER BY CAST(directory_charges AS DECIMAL(10,2)) DESC
LIMIT 10;