How do i create a column 1-10 with a loop? - postgresql

Question

This is an example but I want only a column with 1-10 values without other text columns.
CREATE OR REPLACE FUNCTION somefun_recordset(param_numcount integer)
RETURNS SETOF record AS
$$
DECLARE
result text := '';
searchsql text := '';
var_match record;
BEGIN
searchsql := 'SELECT n || '' down'' As countdown, n as integer
FROM generate_series(' || CAST(param_numcount As text) || ', 1, -1) As n ';
FOR var_match IN EXECUTE(searchsql) LOOP
RETURN NEXT var_match;
END LOOP;
END;
$$
LANGUAGE 'plpgsql' IMMUTABLE;
SELECT r.n , r.countdown
FROM somefun_recordset(10)
As r(countdown text, n integer)
ORDER BY r.n;
How do I create a loop in postgres?

Answer 1

From your current description, you seem to be over-complicating this.
As described in the Postgres manual, the generate_series function can generate a column of values from 10 to 1, like so:
SELECT generate_series(10, 1, -1) as n;
Or using it as a table alias rather than a column alias:
SELECT * FROM generate_series(10, 1, -1) as n;
If you wanted to wrap this in a custom function with only one parameter, it would look like this:
CREATE FUNCTION countdown(param_numcount INT) RETURNS SETOF INT LANGUAGE SQL AS $$
SELECT generate_series(param_numcount, 1, -1);
$$;
Then you would run it as:
SELECT countdown(10) as n;