as oracle doc says supports partial rollup:
partial rollup can roll of sub-totals included. partial rollup uses following syntax:
group expr1, rollup(expr2, expr3);
in case, group clause creates subtotals @ (2+1=3) aggregation levels. is, @ level (expr1, expr2, expr3), (expr1, expr2), , (expr1).
http://docs.oracle.com/cd/e11882_01/server.112/e25554/aggreg.htm#dwhsg8612
does mysql support this?
i tried search in mysql doc , can't find clue.
mysql documentation on with rollup clause quite clear: cannot provide list of columns rollup clause indicate levels want summaries performed.
what can have query rollup clause in subquery , in outer query can remove aggregate rows not need (or can in client application). cannot in having clause, since
because null values in super-aggregate rows placed result set @ such late stage in query processing, cannot test them null values within query itself. example, cannot add having product null query eliminate output super-aggregate rows.
on other hand, null values appear null on client side , can tested such using mysql client programming interface.
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