Select (SQL): Difference between revisions

Revision as of 14:29, 14 December 2021

Revision as of 01:33, 15 December 2021

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For example,

{{sxhl|2=tsql|

sum(population) OVER( PARTITION BY city )

}}

calculates the sum of the populations of all rows having the same ''city'' value as the current row.

Partitions are specified using the '''OVER''' clause which modifies the aggregate. Syntax:

{{sxhl|2=bnf|1=

<OVER_CLAUSE> :: =

OVER ( [ PARTITION BY <expr>, ... ]

[ ORDER BY <expression> ] )

}}

The OVER clause can partition and order the result set. Ordering is used for order-relative functions such as row_number.