Syntax error in postgresql function - postgresql

Question

I am a beginner for postgresql and I would like to create a procedure in sql.
I created a function that inserts a record into a table and it returns the id.
But there is something wrong, I don't want any result except for the output parameter.
CREATE OR REPLACE FUNCTION public."InsertVideo"
(
OUT out_scope_id integer,
IN in_youtubeidvideo varchar[],
IN in_title varchar,
IN in_rating double precision,
IN in_viewcount integer
)
RETURNS integer AS
$$
DECLARE
id INTEGER;
INSERT INTO Video
(
YoutubeIdVideo,
Title,
Rating,
ViewCount,
DataAdded,
ConvertedFlag,
SchedulingFlag
)
VALUES
(
in_youtubeidvideo,
in_title,
in_rating,
in_viewcount,
now(),
false,
false
);
SELECT id := CURRVAL(pg_get_serial_sequence('public.video','IDVideo'));
RETURN id;
$$
LANGUAGE 'sql'
VOLATILE
CALLED ON NULL INPUT
SECURITY INVOKER;

Answer 1

A SQL function can't use variables and you don't need them for this. Changed it to:
CREATE OR REPLACE FUNCTION public."InsertVideo" (
IN in_youtubeidvideo varchar[],
IN in_title varchar,
IN in_rating double precision,
IN in_viewcount integer
) RETURNS integer AS $$
INSERT INTO Video (
YoutubeIdVideo,
Title,
Rating,
ViewCount,
DataAdded,
ConvertedFlag,
SchedulingFlag
) VALUES (
in_youtubeidvideo,
in_title,
in_rating,
in_viewcount,
now(),
false,
false
);
SELECT CURRVAL(pg_get_serial_sequence('public.video','IDVideo'));
$$ LANGUAGE 'sql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;