Two Ways To Rollup
June 16, 2015 Ted Holt
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In Three Powerful SQL Words, I showed how to enhance summary queries with aggregate values over subsets of grouping columns. Today I continue that discussion by showing the two syntaxes of rollup and illustrating the difference between them. First, assume a table of accounting transactions.
select department, account, amount
from xacts2
order by 1, 2
DEPARTMENT ACCOUNT AMOUNT
1 10 200.00
1 10 250.00
1 30 300.00
2 10 125.00
2 20 175.00
2 20 225.00
Here’s a typical summary query using the familiar GROUP BY clause. select department, account, sum(amount) as tamt from xacts2 group by department, account |
