Using user defined function to update table data
postgres=# CREATE TABLE emp ( postgres(# name text, postgres(# salary numeric, postgres(# age integer, postgres(# cubicle point postgres(# ); CREATE TABLE postgres=# postgres=# insert into emp (salary) values(100); INSERT 0 1 postgres=# insert into emp (salary) values(200); INSERT 0 1 postgres=# insert into emp (salary) values(300); INSERT 0 1 postgres=# postgres=# CREATE FUNCTION double_salary(emp) RETURNS numeric AS $$ postgres$# SELECT $1.salary * 2 AS salary; postgres$# $$ LANGUAGE SQL; CREATE FUNCTION postgres=# postgres=# SELECT name, double_salary(ROW(name, salary*1.1, age, cubicle)) AS dream postgres-# FROM emp; name | dream ------+------- | 220.0 | 440.0 | 660.0 (3 rows) postgres=# postgres=# drop function double_salary(emp); DROP FUNCTION postgres=# drop table emp; DROP TABLE postgres=# postgres=#