On Thu, Aug 20, 2015 at 8:03 PM, Stephane Bailliez <sbaill...@gmail.com> wrote:
> Pretty bad subject description... but let me try to explain. > > > I'm trying to figure out what would be the most efficient way to query > data from multiple tables using a foreign key. > > SELECT [...] FROM (SELECT reference_id, [...] FROM table_where_referenced_id_is_a_pk WHERE reference_id EXISTS/IN/JOIN) src LEFT JOIN type1 USING (reference_id) LEFT JOIN type2 USING (reference_id) [...] Or consider whether PostgreSQL Inheritance would work - though basically its a friendly API over the "UNION ALL" query you proposed. David J.
