[SQL] JOINing 2 row sets
Posted: Fri Jan 18, 2019 8:49 pm
Original topic: viewtopic.php?f=13&t=96607&p=462482#p462482
What does the JOIN keyword do with 2 tables?
Why are there so many variants of JOIN in the literature on SQL? Well, many of them are equivalent to each other.
How is it related to the Cartesian Product of the 2 tables?
Is there any difference between the inner join and the selection from 2 tables where A.X=B.Y? Answer: Some old fashioned database engines work more efficiently with JOINs. In HSQL they are equivalent.
What does the JOIN keyword do with 2 tables?
Why are there so many variants of JOIN in the literature on SQL? Well, many of them are equivalent to each other.
How is it related to the Cartesian Product of the 2 tables?
Is there any difference between the inner join and the selection from 2 tables where A.X=B.Y? Answer: Some old fashioned database engines work more efficiently with JOINs. In HSQL they are equivalent.