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https://issues.apache.org/jira/browse/CALCITE-5347?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17624126#comment-17624126
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Julian Hyde commented on CALCITE-5347:
--------------------------------------
On occasion, you may wish to sort by an aggregate function. For example, to
write the following query to find sort departments by their salary budget:
{code:sql}
SELECT deptno, SUM(sal) AS sum_sal
FROM Emp
GROUP BY deptno
ORDER BY sum_sal DESC
{code}
I can't think of a way to support that pattern using the {{SELECT ... BY}}
syntax that wouldn't be confusing/arbitrary.
> Add 'SELECT ... BY', a syntax extension that is shorthand for GROUP BY and
> ORDER BY
> -----------------------------------------------------------------------------------
>
> Key: CALCITE-5347
> URL: https://issues.apache.org/jira/browse/CALCITE-5347
> Project: Calcite
> Issue Type: Bug
> Reporter: Julian Hyde
> Priority: Major
>
> Many people have observed that SQL query syntax is verbose if you want to
> eliminate duplicates and sort. Business intelligence tools often have query
> languages that eliminate duplicates and sort by default; we cannot do that in
> the SQL {{SELECT}} expression, because that would break compatibility. But we
> propose the following variation of {{SELECT}} that is distinguishable from
> regular {{SELECT}} (i.e. queries that use it would be invalid in ordinary
> SQL) but concise and intuitive.
> We propose
> {code:sql}
> SELECT a BY b
> FROM t {code}
> as syntactic sugar for
> {code:sql}
> SELECT b, a
> FROM t
> GROUP BY b
> ORDER BY b{code}
> In the above, {{a}} and {{b}} may be lists of columns, the columns may
> include aliases, and the columns in {{b}} may include sort-key modifiers such
> as {{DESC}} and {{NULLS LAST}}.
> For example,
> {code:sql}
> SELECT e.ename, e.empno BY d.dname AS dept DESC, e.job AS title
> FROM Emp AS e
> JOIN Dept AS d ON e.deptno = d.deptno
> WHERE d.loc = 'CHICAGO'{code}
> is shorthand for
> {code:sql}
> SELECT d.dname AS dept, e.job AS title,
> e.ename, e.empno
> FROM Emp AS e
> JOIN Dept AS d ON e.deptno = d.deptno
> WHERE d.loc = 'CHICAGO'
> GROUP BY d.dname, e.job
> ORDER BY d.dname DESC, e.job {code}
>
> This feature was inspired by [Shakti|https://shakti.com/], a SQL-like
> language by Arthur Whitney, author of the k language.
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