inner outer left right full joins—Oracle?
Can anyone help me understand what the purpose of these types of joins are? I can find plenty of examples but no where explaining why I would use these joins instead of the = (equals) sign for linking tables.
Thank you
If by "use equals sign" you mean something like "select t1.*,t2.* where t1.f1 = t2.f2" then that IS a join, it’s just another way of expressing it.
The main difference between different kinds of join is whether you want values from one table even if the corresponding key does not exist in the other table.
Wikipedia has quite a good page on the subject:
http://en.wikipedia.org/wiki/Database_join
If by "use equals sign" you mean something like "select t1.*,t2.* where t1.f1 = t2.f2" then that IS a join, it’s just another way of expressing it.
The main difference between different kinds of join is whether you want values from one table even if the corresponding key does not exist in the other table.
Wikipedia has quite a good page on the subject:
http://en.wikipedia.org/wiki/Database_join
References :