/SQL/Cannot return non-composite value from function that returns composite type

Cannot return non-composite value from function that returns composite type

--EXAMPLE OF A UPDATE FUNCTION WITH TRIGGER PLPGSQL

CREATE OR REPLACE FUNCTION update_aumentarpreco ()
    RETURNS TRIGGER
    LANGUAGE PLPGSQL
    AS 
    $BODY$
BEGIN
    IF NEW.ps_availqty = 2 THEN
        NEW.ps_supplycost = OLD.ps_supplycost * 0.10;
        RETURN NEW;
    END IF;
    RETURN NULL;
END;
$BODY$ 

CREATE TRIGGER update_aumentarpreco
    BEFORE UPDATE OF ps_availqty ON partsupp
    FOR EACH ROW
    EXECUTE PROCEDURE update_aumentarpreco ();

Similar codes

0 vote255 views1 answer
USING THE NOT CONDITION IN SQL
SQL
0 vote242 views1 answer
Sql file in postgres with pgadmin
SQL
0 vote244 views1 answer
Concatenate columns in table
SQL
0 vote265 views1 answer
Which lock mode is not available in sql
SQL
0 vote263 views1 answer
Postgres select from values
SQL
0 vote255 views2 answers
Sql update multiple tables
SQL
0 vote286 views1 answer
Laravel SQLSTATE[HY000] [2002] No such file or directory (SQL: select * from information_schema.tables where table_schema = testDB and table_name = migrations and table_type = 'BASE TABLE')
SQL
0 vote256 views1 answer
Postgresql alter column nullable
SQL
0 vote286 views1 answer
Modifier une valeur sql
SQL
0 vote249 views1 answer
From _sqlite3 import * ImportError: DLL load failed: Das angegebene Modul wurde nicht gefunden.
SQL