Does it cause a Cartesian join if you include a table nothing is selected from?

Question

Would this be a Cartesian join:

select
dog_t.type
dog_t.breed
date_t.date
from
dog_t,
cat_t,
date_t
where
dog_t.date_key=date_t.date_key

Would including the cat_t table cause a Cartesian join... because it isn't joined to anything?

Answer 1

Yes. You need to add cat_t.date_key=date_t.date_key to avoid the cartesian join.

But you still have a cross-join problem with tables cat_t and dog_t. I would say you should union a separated select from each table.