postgres/src/test/regress/sql/create_function_sql.sql

--
-- CREATE_FUNCTION_SQL
--
-- Assorted tests using SQL-language functions
--

-- All objects made in this test are in temp_func_test schema

CREATE USER regress_unpriv_user;

CREATE SCHEMA temp_func_test;
GRANT ALL ON SCHEMA temp_func_test TO public;

SET search_path TO temp_func_test, public;

--
-- Make sanity checks on the pg_proc entries created by CREATE FUNCTION
--

--
-- ARGUMENT and RETURN TYPES
--
CREATE FUNCTION functest_A_1(text, date) RETURNS bool LANGUAGE 'sql'
       AS 'SELECT $1 = ''abcd'' AND $2 > ''2001-01-01''';
CREATE FUNCTION functest_A_2(text[]) RETURNS int LANGUAGE 'sql'
       AS 'SELECT $1[1]::int';
CREATE FUNCTION functest_A_3() RETURNS bool LANGUAGE 'sql'
       AS 'SELECT false';
SELECT proname, prorettype::regtype, proargtypes::regtype[] FROM pg_proc
       WHERE oid in ('functest_A_1'::regproc,
                     'functest_A_2'::regproc,
                     'functest_A_3'::regproc) ORDER BY proname;

SELECT functest_A_1('abcd', '2020-01-01');
SELECT functest_A_2(ARRAY['1', '2', '3']);
SELECT functest_A_3();

--
-- IMMUTABLE | STABLE | VOLATILE
--
CREATE FUNCTION functest_B_1(int) RETURNS bool LANGUAGE 'sql'
       AS 'SELECT $1 > 0';
CREATE FUNCTION functest_B_2(int) RETURNS bool LANGUAGE 'sql'
       IMMUTABLE AS 'SELECT $1 > 0';
CREATE FUNCTION functest_B_3(int) RETURNS bool LANGUAGE 'sql'
       STABLE AS 'SELECT $1 = 0';
CREATE FUNCTION functest_B_4(int) RETURNS bool LANGUAGE 'sql'
       VOLATILE AS 'SELECT $1 < 0';
SELECT proname, provolatile FROM pg_proc
       WHERE oid in ('functest_B_1'::regproc,
                     'functest_B_2'::regproc,
                     'functest_B_3'::regproc,
		     'functest_B_4'::regproc) ORDER BY proname;

ALTER FUNCTION functest_B_2(int) VOLATILE;
ALTER FUNCTION functest_B_3(int) COST 100;	-- unrelated change, no effect
SELECT proname, provolatile FROM pg_proc
       WHERE oid in ('functest_B_1'::regproc,
                     'functest_B_2'::regproc,
                     'functest_B_3'::regproc,
		     'functest_B_4'::regproc) ORDER BY proname;

--
-- SECURITY DEFINER | INVOKER
--
CREATE FUNCTION functest_C_1(int) RETURNS bool LANGUAGE 'sql'
       AS 'SELECT $1 > 0';
CREATE FUNCTION functest_C_2(int) RETURNS bool LANGUAGE 'sql'
       SECURITY DEFINER AS 'SELECT $1 = 0';
CREATE FUNCTION functest_C_3(int) RETURNS bool LANGUAGE 'sql'
       SECURITY INVOKER AS 'SELECT $1 < 0';
SELECT proname, prosecdef FROM pg_proc
       WHERE oid in ('functest_C_1'::regproc,
                     'functest_C_2'::regproc,
                     'functest_C_3'::regproc) ORDER BY proname;

ALTER FUNCTION functest_C_1(int) IMMUTABLE;	-- unrelated change, no effect
ALTER FUNCTION functest_C_2(int) SECURITY INVOKER;
ALTER FUNCTION functest_C_3(int) SECURITY DEFINER;
SELECT proname, prosecdef FROM pg_proc
       WHERE oid in ('functest_C_1'::regproc,
                     'functest_C_2'::regproc,
                     'functest_C_3'::regproc) ORDER BY proname;

--
-- LEAKPROOF
--
CREATE FUNCTION functest_E_1(int) RETURNS bool LANGUAGE 'sql'
       AS 'SELECT $1 > 100';
CREATE FUNCTION functest_E_2(int) RETURNS bool LANGUAGE 'sql'
       LEAKPROOF AS 'SELECT $1 > 100';
SELECT proname, proleakproof FROM pg_proc
       WHERE oid in ('functest_E_1'::regproc,
                     'functest_E_2'::regproc) ORDER BY proname;

ALTER FUNCTION functest_E_1(int) LEAKPROOF;
ALTER FUNCTION functest_E_2(int) STABLE;	-- unrelated change, no effect
SELECT proname, proleakproof FROM pg_proc
       WHERE oid in ('functest_E_1'::regproc,
                     'functest_E_2'::regproc) ORDER BY proname;

ALTER FUNCTION functest_E_2(int) NOT LEAKPROOF;	-- remove leakproof attribute
SELECT proname, proleakproof FROM pg_proc
       WHERE oid in ('functest_E_1'::regproc,
                     'functest_E_2'::regproc) ORDER BY proname;

-- it takes superuser privilege to turn on leakproof, but not to turn off
ALTER FUNCTION functest_E_1(int) OWNER TO regress_unpriv_user;
ALTER FUNCTION functest_E_2(int) OWNER TO regress_unpriv_user;

SET SESSION AUTHORIZATION regress_unpriv_user;
SET search_path TO temp_func_test, public;
ALTER FUNCTION functest_E_1(int) NOT LEAKPROOF;
ALTER FUNCTION functest_E_2(int) LEAKPROOF;

CREATE FUNCTION functest_E_3(int) RETURNS bool LANGUAGE 'sql'
       LEAKPROOF AS 'SELECT $1 < 200';	-- fail

RESET SESSION AUTHORIZATION;

--
-- CALLED ON NULL INPUT | RETURNS NULL ON NULL INPUT | STRICT
--
CREATE FUNCTION functest_F_1(int) RETURNS bool LANGUAGE 'sql'
       AS 'SELECT $1 > 50';
CREATE FUNCTION functest_F_2(int) RETURNS bool LANGUAGE 'sql'
       CALLED ON NULL INPUT AS 'SELECT $1 = 50';
CREATE FUNCTION functest_F_3(int) RETURNS bool LANGUAGE 'sql'
       RETURNS NULL ON NULL INPUT AS 'SELECT $1 < 50';
CREATE FUNCTION functest_F_4(int) RETURNS bool LANGUAGE 'sql'
       STRICT AS 'SELECT $1 = 50';
SELECT proname, proisstrict FROM pg_proc
       WHERE oid in ('functest_F_1'::regproc,
                     'functest_F_2'::regproc,
                     'functest_F_3'::regproc,
                     'functest_F_4'::regproc) ORDER BY proname;

ALTER FUNCTION functest_F_1(int) IMMUTABLE;	-- unrelated change, no effect
ALTER FUNCTION functest_F_2(int) STRICT;
ALTER FUNCTION functest_F_3(int) CALLED ON NULL INPUT;
SELECT proname, proisstrict FROM pg_proc
       WHERE oid in ('functest_F_1'::regproc,
                     'functest_F_2'::regproc,
                     'functest_F_3'::regproc,
                     'functest_F_4'::regproc) ORDER BY proname;


-- pg_get_functiondef tests

SELECT pg_get_functiondef('functest_A_1'::regproc);
SELECT pg_get_functiondef('functest_B_3'::regproc);
SELECT pg_get_functiondef('functest_C_3'::regproc);
SELECT pg_get_functiondef('functest_F_2'::regproc);


--
-- SQL-standard body
--
CREATE FUNCTION functest_S_1(a text, b date) RETURNS boolean
    LANGUAGE SQL
    RETURN a = 'abcd' AND b > '2001-01-01';
CREATE FUNCTION functest_S_2(a text[]) RETURNS int
    RETURN a[1]::int;
CREATE FUNCTION functest_S_3() RETURNS boolean
    RETURN false;
CREATE FUNCTION functest_S_3a() RETURNS boolean
    BEGIN ATOMIC
        ;;RETURN false;;
    END;

CREATE FUNCTION functest_S_10(a text, b date) RETURNS boolean
    LANGUAGE SQL
    BEGIN ATOMIC
        SELECT a = 'abcd' AND b > '2001-01-01';
    END;

CREATE FUNCTION functest_S_13() RETURNS boolean
    BEGIN ATOMIC
        SELECT 1;
        SELECT false;
    END;

-- check display of function arguments in sub-SELECT
CREATE TABLE functest1 (i int);
CREATE FUNCTION functest_S_16(a int, b int) RETURNS void
    LANGUAGE SQL
    BEGIN ATOMIC
        INSERT INTO functest1 SELECT a + $2;
    END;

-- error: duplicate function body
CREATE FUNCTION functest_S_xxx(x int) RETURNS int
    LANGUAGE SQL
    AS $$ SELECT x * 2 $$
    RETURN x * 3;

-- polymorphic arguments not allowed in this form
CREATE FUNCTION functest_S_xx(x anyarray) RETURNS anyelement
    LANGUAGE SQL
    RETURN x[1];

-- check reporting of parse-analysis errors
CREATE FUNCTION functest_S_xx(x date) RETURNS boolean
    LANGUAGE SQL
    RETURN x > 1;

-- tricky parsing
CREATE FUNCTION functest_S_15(x int) RETURNS boolean
LANGUAGE SQL
BEGIN ATOMIC
    select case when x % 2 = 0 then true else false end;
END;

SELECT functest_S_1('abcd', '2020-01-01');
SELECT functest_S_2(ARRAY['1', '2', '3']);
SELECT functest_S_3();

SELECT functest_S_10('abcd', '2020-01-01');
SELECT functest_S_13();

SELECT pg_get_functiondef('functest_S_1'::regproc);
SELECT pg_get_functiondef('functest_S_2'::regproc);
SELECT pg_get_functiondef('functest_S_3'::regproc);
SELECT pg_get_functiondef('functest_S_3a'::regproc);
SELECT pg_get_functiondef('functest_S_10'::regproc);
SELECT pg_get_functiondef('functest_S_13'::regproc);
SELECT pg_get_functiondef('functest_S_15'::regproc);
SELECT pg_get_functiondef('functest_S_16'::regproc);

DROP TABLE functest1 CASCADE;

-- test with views
CREATE TABLE functest3 (a int);
INSERT INTO functest3 VALUES (1), (2);
CREATE VIEW functestv3 AS SELECT * FROM functest3;

CREATE FUNCTION functest_S_14() RETURNS bigint
    RETURN (SELECT count(*) FROM functestv3);

SELECT functest_S_14();

DROP TABLE functest3 CASCADE;


-- information_schema tests

CREATE FUNCTION functest_IS_1(a int, b int default 1, c text default 'foo')
    RETURNS int
    LANGUAGE SQL
    AS 'SELECT $1 + $2';

CREATE FUNCTION functest_IS_2(out a int, b int default 1)
    RETURNS int
    LANGUAGE SQL
    AS 'SELECT $1';

CREATE FUNCTION functest_IS_3(a int default 1, out b int)
    RETURNS int
    LANGUAGE SQL
    AS 'SELECT $1';

SELECT routine_name, ordinal_position, parameter_name, parameter_default
    FROM information_schema.parameters JOIN information_schema.routines USING (specific_schema, specific_name)
    WHERE routine_schema = 'temp_func_test' AND routine_name ~ '^functest_is_'
    ORDER BY 1, 2;

DROP FUNCTION functest_IS_1(int, int, text), functest_IS_2(int), functest_IS_3(int);

-- routine usage views

CREATE FUNCTION functest_IS_4a() RETURNS int LANGUAGE SQL AS 'SELECT 1';
CREATE FUNCTION functest_IS_4b(x int DEFAULT functest_IS_4a()) RETURNS int LANGUAGE SQL AS 'SELECT x';

CREATE SEQUENCE functest1;
CREATE FUNCTION functest_IS_5(x int DEFAULT nextval('functest1'))
    RETURNS int
    LANGUAGE SQL
    AS 'SELECT x';

CREATE FUNCTION functest_IS_6()
    RETURNS int
    LANGUAGE SQL
    RETURN nextval('functest1');

CREATE TABLE functest2 (a int, b int);

CREATE FUNCTION functest_IS_7()
    RETURNS int
    LANGUAGE SQL
    RETURN (SELECT count(a) FROM functest2);

SELECT r0.routine_name, r1.routine_name
  FROM information_schema.routine_routine_usage rru
       JOIN information_schema.routines r0 ON r0.specific_name = rru.specific_name
       JOIN information_schema.routines r1 ON r1.specific_name = rru.routine_name
  WHERE r0.routine_schema = 'temp_func_test' AND
        r1.routine_schema = 'temp_func_test'
  ORDER BY 1, 2;
SELECT routine_name, sequence_name FROM information_schema.routine_sequence_usage
  WHERE routine_schema = 'temp_func_test'
  ORDER BY 1, 2;
SELECT routine_name, table_name, column_name FROM information_schema.routine_column_usage
  WHERE routine_schema = 'temp_func_test'
  ORDER BY 1, 2;
SELECT routine_name, table_name FROM information_schema.routine_table_usage
  WHERE routine_schema = 'temp_func_test'
  ORDER BY 1, 2;

DROP FUNCTION functest_IS_4a CASCADE;
DROP SEQUENCE functest1 CASCADE;
DROP TABLE functest2 CASCADE;


-- overload
CREATE FUNCTION functest_B_2(bigint) RETURNS bool LANGUAGE 'sql'
       IMMUTABLE AS 'SELECT $1 > 0';

DROP FUNCTION functest_b_1;
DROP FUNCTION functest_b_1;  -- error, not found
DROP FUNCTION functest_b_2;  -- error, ambiguous


-- CREATE OR REPLACE tests

CREATE FUNCTION functest1(a int) RETURNS int LANGUAGE SQL AS 'SELECT $1';
CREATE OR REPLACE FUNCTION functest1(a int) RETURNS int LANGUAGE SQL WINDOW AS 'SELECT $1';
CREATE OR REPLACE PROCEDURE functest1(a int) LANGUAGE SQL AS 'SELECT $1';
DROP FUNCTION functest1(a int);


-- inlining of set-returning functions

CREATE TABLE functest3 (a int);
INSERT INTO functest3 VALUES (1), (2), (3);

CREATE FUNCTION functest_sri1() RETURNS SETOF int
LANGUAGE SQL
STABLE
AS '
    SELECT * FROM functest3;
';

SELECT * FROM functest_sri1();
EXPLAIN (verbose, costs off) SELECT * FROM functest_sri1();

CREATE FUNCTION functest_sri2() RETURNS SETOF int
LANGUAGE SQL
STABLE
BEGIN ATOMIC
    SELECT * FROM functest3;
END;

SELECT * FROM functest_sri2();
EXPLAIN (verbose, costs off) SELECT * FROM functest_sri2();

DROP TABLE functest3 CASCADE;


-- Check behavior of VOID-returning SQL functions

CREATE FUNCTION voidtest1(a int) RETURNS VOID LANGUAGE SQL AS
$$ SELECT a + 1 $$;
SELECT voidtest1(42);

CREATE FUNCTION voidtest2(a int, b int) RETURNS VOID LANGUAGE SQL AS
$$ SELECT voidtest1(a + b) $$;
SELECT voidtest2(11,22);

-- currently, we can inline voidtest2 but not voidtest1
EXPLAIN (verbose, costs off) SELECT voidtest2(11,22);

CREATE TEMP TABLE sometable(f1 int);

CREATE FUNCTION voidtest3(a int) RETURNS VOID LANGUAGE SQL AS
$$ INSERT INTO sometable VALUES(a + 1) $$;
SELECT voidtest3(17);

CREATE FUNCTION voidtest4(a int) RETURNS VOID LANGUAGE SQL AS
$$ INSERT INTO sometable VALUES(a - 1) RETURNING f1 $$;
SELECT voidtest4(39);

TABLE sometable;

CREATE FUNCTION voidtest5(a int) RETURNS SETOF VOID LANGUAGE SQL AS
$$ SELECT generate_series(1, a) $$ STABLE;
SELECT * FROM voidtest5(3);

-- Regression tests for bugs:

-- Check that arguments that are R/W expanded datums aren't corrupted by
-- multiple uses.  This test knows that array_append() returns a R/W datum
-- and will modify a R/W array input in-place.  We use SETOF to prevent
-- inlining of the SQL function.
CREATE FUNCTION double_append(anyarray, anyelement) RETURNS SETOF anyarray
LANGUAGE SQL IMMUTABLE AS
$$ SELECT array_append($1, $2) || array_append($1, $2) $$;

SELECT double_append(array_append(ARRAY[q1], q2), q3)
  FROM (VALUES(1,2,3), (4,5,6)) v(q1,q2,q3);

-- Things that shouldn't work:

CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
    AS 'SELECT ''not an integer'';';

CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
    AS 'not even SQL';

CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
    AS 'SELECT 1, 2, 3;';

CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
    AS 'SELECT $2;';

CREATE FUNCTION test1 (int) RETURNS int LANGUAGE SQL
    AS 'a', 'b';

-- Cleanup
DROP SCHEMA temp_func_test CASCADE;
DROP USER regress_unpriv_user;
RESET search_path;