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
.
Other forms: over
clause (inline), window
clause
Product specific clause: qualify
.
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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