Question

I have a products schema and some tables there.
Each table in products schema has an id, and by this id I can get this table name, e.g.

products
    \ product1
    \ product2
    \ product3

I need to select info from dynamic access to appropriate product, e.g.

SELECT * FROM 'products.'(SELECT id from categories WHERE id = 7);

Of course, this doesn’t work…
How I can do something like that in PostgreSQL?

Answer 1

OK, I found a solution:

CREATE OR REPLACE FUNCTION getProductById(cid int) RETURNS RECORD AS $$
    DECLARE
    result RECORD;

    BEGIN
        EXECUTE 'SELECT * FROM ' || (SELECT ('products.' || (select category_name from category where category_id = cid) || '_view')::regclass) INTO result;

        RETURN result;
    END;
$$ LANGUAGE plpgsql;

and to select:

SELECT * FROM getProductById(7) AS b (category_id int, ... );

works for PostgreSQL 9.x