For the first time I'm trying to create function in PostgreSQL:
This function must accept parameter with array type. Array contains sequence of biginteger values. Size of array not arbitrary, but known in advance.
create function get_total (cols ARRAY) returns biginteger AS
$BODY$
begin
// Some logics
end;
$BODY$
Usage in query
select
stats.value1,
stats.value2,
get_total(array_agg(ARRAY[stats.value2, stats.value1]))
from stats;
It returns error:
type cols[] does not exist
SQL state: 42704
When I run in Select only array_agg(ARRAY[stats.value2, stats.value1]), I see, that array created successfully. So the problem in function parameter.
What am I doing wrong?
CodePudding user response:
The syntax cols ARRAY
is the same as cols[]
and means “an array with elements of type cols
”. That's why you get that error message for the function definition.
If the element type is bigint
, the function should be defined as
CREATE FUNCTION get_total(cols bigint ARRAY) RETURNS bigint
CodePudding user response:
You have to declare the parameter as bigint[]
, which reads an array of type bigint
e.g.
CREATE OR REPLACE FUNCTION get_total (bigint[])
RETURNS bigint AS
$$
BEGIN
-- your fancy logic goes here
END;
$$ LANGUAGE plpgsql
Function call:
SELECT get_total(ARRAY[1111111111111,1111111111111]);
An elegant alternative is to declare the parameter as VARIADIC
. Doing so you may call your function with multiple parameters,e.g.:
CREATE OR REPLACE FUNCTION get_total (VARIADIC bigint[])
RETURNS bigint AS
$$
BEGIN
-- your fancy logic goes here
END;
$$ LANGUAGE plpgsql;
Function call:
SELECT get_total(1111111111111,1111111111111,1111111111111);
Demo: db<>fiddle