Postgres function to give Fibonacci Sequence in SQL.

fib.sql

create or replace function fib(n int)
returns setof int as $$ 
declare 
    a int := 0;
    b int := 1;
begin 
    return next 0;
    return next 1;
    while a < n loop
        a := a + b;
        return next a;
        b := b + a;
        return next b; 
    end loop;
end;
$$ language plpgsql;

select * from fib(10);