Can Multiple Indexes Work Together?

Question

Suppose I have a database table with two fields, \"foo\" and \"bar\". Neither of them are unique, but each of them are indexed. However, rather than being indexed together, th

Answer 1

It's better than that.

Index Seeks are always quicker than full table scans. So behind the scenes Oracle (and SQL server for that matter) will first locate the range of rows on both indices. It will then look at which range is shorter (seeing that it's an inner join), and it will iterate the shorter range to find the matches with the larger of the two.