Can I use… window clause


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The window clause allows to centralize and reuse window definitions. It is the last clause of <table expression>—i.e. it follows the having clause if present.

 SELECT MIN(x) OVER window_name
      , MAX(x) OVER window_name
   FROM …
[ WHERE …    ]
[ GROUP BY … ]
[HAVING …    ]
 WINDOW window_name AS ([PARTITION BY …] [ORDER BY …] …) 

Both window functions, min and max, use the same window definition.

Normative References

The window clause is defined in ISO/IEC 9075:2016-2 as part of optional feature T612, “Advanced OLAP operations”.

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