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Xiao Li commented on SPARK-27986: --------------------------------- There is a blog to describe this feature too. [https://blog.jooq.org/2014/12/30/the-awesome-postgresql-9-4-sql2003-filter-clause-for-aggregate-functions/] > Support Aggregate Expressions with filter > ----------------------------------------- > > Key: SPARK-27986 > URL: https://issues.apache.org/jira/browse/SPARK-27986 > Project: Spark > Issue Type: Sub-task > Components: SQL > Affects Versions: 3.0.0 > Reporter: Yuming Wang > Priority: Major > > 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: > {noformat} > 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 ) ]{noformat} > [https://www.postgresql.org/docs/current/sql-expressions.html#SYNTAX-AGGREGATES] > -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org