Julian Hyde created CALCITE-5347:
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             Summary: Add 'SELECT ... BY', a syntax extension to eliminate 
duplicates and sort
                 Key: CALCITE-5347
                 URL: https://issues.apache.org/jira/browse/CALCITE-5347
             Project: Calcite
          Issue Type: Bug
            Reporter: Julian Hyde


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 that
{code:java}
SELECT a BY b
FROM t {code}
is syntactic sugar for
{code:java}
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{}}}.

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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