Can I use… window … as (<existing window name> …)


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Definitions in the window clause can inherit declarations from previous window names of the same clause.

 SELECT COUNT(*) OVER tenant
      , SUM(x) OVER past
   FROM …
 WINDOW tenant AS (PARTITION BY …)
      , past AS (tenant ORDER BY …) 

The window name past inherits the partition by clause from tenant.

Normative References

The window clause, including the ability to refer to existing window names, is defined in ISO/IEC 9075:2016-2 as part of optional feature T612, “Advanced OLAP operations”.

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