This is mainly for my information so I can find it when I need it next time.

You have to have a query that groups over something, preferably doing a SUM() (haven't tried it with anything else) and put WITH ROLLUP at the end. Do something like:

SELECT name, purchaseid, sum(amount) from purchases group by name, purchaseid WITH ROLLUP

You will get results like:

A    1    10

A    2    10

A    NULL 20    <-- subtotal

B    1    15

B    NULL 15    <-- subtotal

NULL NULL 35    <-- grand total

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