Description
An aggregate expression represents the application of an aggregate function across the rows selected by a query. An aggregate function reduces multiple inputs to a single output value, such as the sum or average of the inputs. The syntax of an aggregate expression is one of the following:
aggregate_name (expression [ , ... ] [ order_by_clause ] ) [ FILTER ( WHERE filter_clause ) ] aggregate_name (ALL expression [ , ... ] [ order_by_clause ] ) [ FILTER ( WHERE filter_clause ) ] aggregate_name (DISTINCT expression [ , ... ] [ order_by_clause ] ) [ FILTER ( WHERE filter_clause ) ] aggregate_name ( * ) [ FILTER ( WHERE filter_clause ) ] aggregate_name ( [ expression [ , ... ] ] ) WITHIN GROUP ( order_by_clause ) [ FILTER ( WHERE filter_clause ) ]
https://www.postgresql.org/docs/current/sql-expressions.html#SYNTAX-AGGREGATES
I find this feature is also an ANSI SQL standard.
<aggregate function> ::= COUNT <left paren> <asterisk> <right paren> [ <filter clause> ] | <general set function> [ <filter clause> ] | <binary set function> [ <filter clause> ] | <ordered set function> [ <filter clause> ] | <array aggregate function> [ <filter clause> ] | <row pattern count function> [ <filter clause> ]
Attachments
Issue Links
- contains
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SPARK-28500 adds support for `filter` clause
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- Resolved
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- is related to
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SPARK-30027 Support codegen for filter exprs in HashAggregateExec
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- Resolved
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- links to
(1 links to)