Scenario: I have two MySQL tables. Both of them have an index on the column called "foo."
1. I run a SELECT query and use a JOIN clause naming "foo" in the two tables. I get a results set giving the intersection of the tables on "foo."
2. I remove the index from one or both of the tables and rerun the query in #1.
Will I get the same results set from the second (unindexed) SELECT? Or does the presence of an index affect the results of JOIN?