Aggregate function filters

You can use a FILTER clause on an aggregate function to specify which rows are sent to an aggregate function. Rows for which the filter_clause evaluates to true contribute to the aggregation.

Temporal filters cannot be used in aggregate function filters.

Syntax

Examples

SELECT  COUNT(*) AS unfiltered,  -- The FILTER guards the evaluation which might otherwise error.  COUNT(1 / (5 - i)) FILTER (WHERE i < 5) AS filtered FROM generate_series(1,10) AS s(i)