Aggregate Range

...?? ... Same as

SELECT MAX(num_value)-MIN(num_value) AS range_val FROM t; 

range()

Snippets

Aggregate Range

Works with PostgreSQL

Any version

Written in

SQL

Depends on

Nothing

CREATE OR REPLACE FUNCTION _final_range(numeric[])  RETURNS numeric AS $$  SELECT MAX(val) - MIN(val)  FROM unnest($1) val; $$ LANGUAGE 'sql' IMMUTABLE; -- Add aggregate CREATE AGGREGATE range(numeric) (  SFUNC=array_append, --Function to call for each row. Just builds the array  STYPE=numeric[],  FINALFUNC=_final_range, --Function to call after everything has been added to array  INITCOND='{}' --Initialize an empty array when starting ); 

Usage

SELECT range(num_value) AS range_val FROM t; 

Caution

If you are on PostgreSQL 8.3 or earlier, you will need to add the Array Unnest function.

See Also

• Aggregate Mode
• Aggregate Median