I've got a postgresql stored procedure, which is returning an integer.
When I call that function, the result is returned with the function name as column name.
For example the name of the function is: "add-person". The column name, when invoking the function, is "add-person".
Is there a way to make the database return the integer with a self-choosen column name? For example "id"?
I think it is pretty easy, but I currently miss the forests for the trees..
Edit:
What i'd missed to tell, is that the return value is a variable, like so:
CREATE OR REPLACE FUNCTION "scheme"."add-person"(arggivenname character varying, argfamilyname character varying) RETURNS integer AS
$BODY$
DECLARE
varResponse integer;
BEGIN
-- Operations before
INSERT INTO "scheme"."table"
(
given_name,
family_name
)
VALUES
(
arggivenname,
argfamilyname
)
RETURNING
"id"
INTO
varResponse;
-- Operations after
RETURN varResponse;
END;
$BODY$
LANGUAGE plpgsql VOLATILE COST 100;
You can us the AS statement for that. That means:
Select add-person() AS yourcolumnname
To have a named column from a function it is necessary to create a type and return that type from the function
create type mytype as (mycolumn integer);
create or replace function ri()
returns mytype as $$
select 1;
$$ language sql;
select * from ri();
mycolumn
----------
1
Edit
Or much simpler without the type creation as in #pozs comment:
create or replace function ri(out mycolumn integer)
as $$
select 1;
$$ language sql;
Related
I've created a function like this.
create or replace function pesquisar_imoveis_residenciais_venda()
returns table(preco decimal)
as $$
begin
select preco from casa_venda;
end; $$
language 'plpgsql';
When I call it
select pesquisar_imoveis_residenciais_venda()
I get the column reference preco is ambiguous.
I've visited some related question. But they are too difficult to follow, very complex functions.
The columns defined in the RETURNS QUERY clause are variables in the PL/pgSQL function body, so the ambiguity is between the variable preco and the table column of the same name. You need to qualify the reference with either the table name or the function name to disambiguate that.
But your function definition has other issues. I think you want:
create or replace function pesquisar_imoveis_residenciais_venda()
returns table(preco decimal)
as $$
begin
return query select cv.preco from casa_venda cv;
end; $$
language 'plpgsql';
select *
from pesquisar_imoveis_residenciais_venda();
Here is a db<>fiddle.
You can override the plpgsql.variable_conflict configuration parameter:
create or replace function pesquisar_imoveis_residenciais_venda()
returns table(preco decimal)
as $$
#variable_conflict use_column
begin
select preco from casa_venda;
end; $$
language 'plpgsql';
This assumes you want to use the column value and not the variable value. If that's not the case then specify #variable_conflict use_variable instead.
See the docs for further details.
it means column name Preco in table casa_venda is not exist or exist more than 1 time.
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?
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
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
This is my query.
select origindept, `count(am_course_name)` as total_course
from am_courseoffered
group by origindept;
I am trying to create a function who will return this query.
CREATE OR REPLACE FUNCTION getcourse ()
RETURNS TABLE (
course_origindept character varying,
course_ count(am_course_name) character varying
)
AS $$
BEGIN
RETURN QUERY select origindept, count(am_course_name) as number_total_course
from am_courseoffered
group by origindept;
END; $$
LANGUAGE 'plpgsql';
There are some error in my function.
ERROR: syntax error at or near "character"
LINE 4: course_ count(am_course_name) character varying
How i create function who will return this query.
Off the top of my head, the count function should return a datatype of bigint, so I would think declaring the count as a varchar would cause a datatype mismatch. Something like this should fix that:
CREATE OR REPLACE FUNCTION getcourse ()
RETURNS TABLE (
course_origindept character varying,
course_count bigint -- change here
) AS $$
BEGIN
RETURN QUERY
select origindept, count(am_course_name) as number_total_course
from am_courseoffered
group by origindept;
END;
$$
LANGUAGE plpgsql;
I do have to ask, though... is this an academic exercise to understand functions? The use case is questionable enough, as a view would be more appropriate.
I have a function like this
CREATE OR REPLACE FUNCTION factors_apart_sa()
RETURNS TABLE(surf_area integer, sa_factor numeric) AS
$BODY$
BEGIN
RETURN QUERY SELECT factors_apart_sa.surf_area, factors_apart_sa.sa_factor FROM factors_apart_sa;
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100
ROWS 1000;
After calling this function I get an error:
column reference "factors_apart_sa.surf_area" is ambiguous
How come is it still ambiguous if I have specified the table name.
Here is the table factors_apart_sa:
CREATE TABLE factors_apart_sa
(
factors_apar_sa_id bigserial NOT NULL,
surf_area integer,
sa_factor numeric(19,4) NOT NULL
)
Use a table alias:
CREATE OR REPLACE FUNCTION factors_apart_sa()
RETURNS TABLE(surf_area integer, sa_factor numeric) AS
$BODY$
BEGIN
RETURN QUERY SELECT f.surf_area, f.sa_factor FROM factors_apart_sa f;
END;
$BODY$
LANGUAGE plpgsql VOLATILE;
It is not a good idea to have the same names for a table and a function;
To call a function returnig set of rows place it in a FROM clause:
select f.*
from factors_apart_sa() f;
I have the table with some columns:
--table
create table testz
(
ID uuid,
name text
);
Note: I want to insert ID values by passing as a parameter to the function. Because I am generating the ID value
in the front end by using uuid_generate_v4(). So I need to pass the generated value to the function to insert
into the table
My bad try:
--function
CREATE OR REPLACE FUNCTION testz
(
p_id varchar(50),
p_name text
)
RETURNS VOID AS
$BODY$
BEGIN
INSERT INTO testz values(p_id,p_name);
END;
$BODY$
LANGUAGE PLPGSQL;
--EXECUTE FUNCTION
SELECT testz('24f9aa53-e15c-4813-8ec3-ede1495e05f1','Abc');
Getting an error:
ERROR: column "id" is of type uuid but expression is of type character varying
LINE 1: INSERT INTO testz values(p_id,p_name)
You need a simple cast to make sure PostgreSQL understands, what you want to insert:
INSERT INTO testz values(p_id::uuid, p_name); -- or: CAST(p_id AS uuid)
Or (preferably) you need a function, with exact parameter types, like:
CREATE OR REPLACE FUNCTION testz(p_id uuid, p_name text)
RETURNS VOID AS
$BODY$
BEGIN
INSERT INTO testz values(p_id, p_name);
END;
$BODY$
LANGUAGE PLPGSQL;
With this, a cast may be needed at the calling side (but PostgreSQL usually do better automatic casts with function arguments than inside INSERT statements).
SQLFiddle
If your function is that simple, you can use SQL functions too:
CREATE OR REPLACE FUNCTION testz(uuid, text) RETURNS VOID
LANGUAGE SQL AS 'INSERT INTO testz values($1, $2)';