I am having problems with MySQL inconsistently choosing the wrong index, or no index at all, for queries on tables with 20 million rows. Would it be a good idea for me to set max_seeks_for_key to 1 (or something less than 4 billion), in order to force MySQL to use an index? We are using InnoDB.
Since InnoDB has clustered indexes, is there ever a good reason for MySQL to prefer a table scan? Thanks, -Bob
