Hi, you can use a hint to force specific index usage : http://lib.hutech.edu.vn/ebookonline/ebook1/0596003064/hpmysql-CHP-5-SECT-4.html
But this is not a good idea since data change and index selectivity can become bad. Also, if the index scan + the table scan is bigger than a full table scan, even you will prefer FTS. So, according to selectivity, usage of an index can be a very bad idea. Thsi depends on how many rows your query retreives among the count(*) of the table. Mathias Selon Bob O'Neill <[EMAIL PROTECTED]>: > 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 -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
