I have a SQL with several (21) items in the SELECT part JOINing 6 tables.
I want to sum one of the fields; SUM(cost) and GROUP BY cost.
Can I do this without having to use all the rest of the fields in the GROUP BY ?
SELECT a.field1, SUM(a,field2), b.field1, c.field4,...(there's also a subquery in here)
FROM table1 AS a
LEFT JOIN table2 AS b
GROUP BY a.field2
- or do I ave to use another subquery?