Correlated SQL derived tables, which are not ANSI standard, are not supported. For example, the following query is not supported because it references the SQL derived table dt_publishers2 inside the derived table expression for dt_publishers1:
select * from (select * from titles where titles.pub_id = dt_publishers2.pub_id) dt_publishers1, (select * from publishers where city = "Boston") dt_publishers2 where dt_publishers1.pub_id = dt_publishers2.pub_id
Similarly, the following query is not supported because the derived table expression for dt_publishers references the publishers_pub_id column, which is outside the scope of the SQL derived table:
select * from publishers where pub_id in (select pub_id from (select pub_id from titles where pub_id = publishers.pub_id) dt_publishers)
The following query illustrates proper referencing and is supported:
select * from publishers where pub_id in (select pub_id from (select pub_id from titles) dt_publishers where pub_id = publishers.pub_id)
