Absolutely not. First, you have the overhead of maintaining the two
tables. Second, MySQL doesn't know that they are identical tables, so
it will try to cache both of them. On a self join, MySQL does know they
are identical, so it will only need to load the data into memory once.
If there is en
Hello,
I have a query that will be used alot on my website that involves a 42
million record table being self-joined. The primary table instance will be
limited by an index resulting in 1 to about 50,000 rows being selected, then
joined to the second instance of the table, which will retrieve
