src/test/regress/expected/default_parameters.out

-- -----------------------------------------------------------------
-- Test function default parameters
--
-- PostgreSQL's 'polymorphism' test mostly covers default
-- parameters. This file contains a few extra tests.
-- -----------------------------------------------------------------
-- inout argmode test:
create function dfunc(a inout int default 10, b int = 2) as $$ select $1 + $2; $$ language sql;
select dfunc();
 dfunc 
-------
    12
(1 row)

select dfunc(4);
 dfunc 
-------
     6
(1 row)

select dfunc(4,5);
 dfunc 
-------
     9
(1 row)

\df dfunc
                                     List of functions
 Schema | Name  | Result data type |               Argument data types               | Type 
--------+-------+------------------+-------------------------------------------------+------
 public | dfunc | integer          | INOUT a integer DEFAULT 10, b integer DEFAULT 2 | func
(1 row)

drop function dfunc(int, int);
-- ambiguity should be reported only if there's not a better match available
create function dfunc(text) returns text as $$ select $1; $$ language sql;
create function dfunc(int = 1, int = 2) returns int as $$ select 2; $$ language sql;
create function dfunc(int = 1, int = 2, int = 3, int = 4) returns int as $$ select 4; $$ language sql;
-- now, dfunc(nargs = 2) and dfunc(nargs = 4) are ambiguous when called
-- with 0 to 2 arguments with input type int
select dfunc('Hi');	-- ok, input type text
 dfunc 
-------
 Hi
(1 row)

select dfunc();  -- fail
ERROR:  function dfunc() is not unique
LINE 1: select dfunc();
               ^
HINT:  Could not choose a best candidate function. You might need to add explicit type casts.
select dfunc(1);  -- fail
ERROR:  function dfunc(integer) is not unique
LINE 1: select dfunc(1);
               ^
HINT:  Could not choose a best candidate function. You might need to add explicit type casts.
select dfunc(1, 2);  -- fail
ERROR:  function dfunc(integer, integer) is not unique
LINE 1: select dfunc(1, 2);
               ^
HINT:  Could not choose a best candidate function. You might need to add explicit type casts.
select dfunc(1, 2, 3);  -- ok
 dfunc 
-------
     4
(1 row)

select dfunc(1, 2, 3, 4);  -- ok
 dfunc 
-------
     4
(1 row)

drop function dfunc(text);
drop function dfunc(int, int);
drop function dfunc(int, int, int, int);
-- check defaults for variadics
create function dfunc(a variadic int[]) returns int as
$$ select array_upper($1, 1) $$ language sql;
select dfunc();  -- fail
ERROR:  function dfunc() does not exist
LINE 1: select dfunc();
               ^
HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
select dfunc(10);
 dfunc 
-------
     1
(1 row)

select dfunc(10,20);
 dfunc 
-------
     2
(1 row)

create or replace function dfunc(a variadic int[] default '{44,88,99}'::int[]) returns int as $$ select array_upper($1, 1) $$ language sql;
select dfunc();  -- now ok
 dfunc 
-------
     3
(1 row)

select dfunc(10);
 dfunc 
-------
     1
(1 row)

select dfunc(10,20);
 dfunc 
-------
     2
(1 row)

-- can change default value
create or replace function dfunc(a variadic int[] default '{44,55,88,99}'::int[]) returns int as $$ select array_upper($1, 1) $$ language sql;
select dfunc();
 dfunc 
-------
     4
(1 row)

drop function dfunc(a variadic int[]);
-- test expression
create function dfunc(a int, b double precision default random()*10) returns double precision as $$ select $1+$2; $$ language sql;
\df dfunc
                                                  List of functions
 Schema | Name  | Result data type |                            Argument data types                            | Type 
--------+-------+------------------+---------------------------------------------------------------------------+------
 public | dfunc | double precision | a integer, b double precision DEFAULT (random() * (10)::double precision) | func
(1 row)

create view dview as select random()*10, dfunc(4);
select pg_get_viewdef('dview',true);
                     pg_get_viewdef                     
--------------------------------------------------------
  SELECT random() * 10::double precision AS "?column?",+
     dfunc(4) AS dfunc;
(1 row)

-- need drop cascade
drop function dfunc(int, double precision);
ERROR:  cannot drop function dfunc(integer,double precision) because other objects depend on it
DETAIL:  view dview depends on function dfunc(integer,double precision)
HINT:  Use DROP ... CASCADE to drop the dependent objects too.
drop function dfunc(int, double precision) cascade;
NOTICE:  drop cascades to view dview