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WPMY MySQL Handler_read_rnd and Handler_read_rnd_next (2 posts)

  1. cogmios
    Member
    Posted 14 years ago #

    Among others I see in Mysq:

    Handler_read_rnd  	665 k  	 The number of requests to read a row based on a fixed position. This is high if you are doing a lot of queries that require sorting of the result. You probably have a lot of queries that require MySQL to scan whole tables or you have joins that don't use keys properly.
    Handler_read_rnd_next 	8 M 	The number of requests to read the next row in the data file. This is high if you are doing a lot of table scans. Generally this suggests that your tables are not properly indexed or that your queries are not written to take advantage of the indexes you have.

    Im pretty much using the default install. So I guess more people have these ones in their MySQL reports.

    Is there an index i can sdd somewhere to lowere these warnings?

  2. SteveAtty
    Member
    Posted 14 years ago #

    As the options table doesn't have an index on the autoload column then you are always going to get a lot of requests where no index is being used.

    If you enable the query without indexes option in your MySQL config file you'll be able to see which queries are causing problems.

About this Topic

  • Started 14 years ago by cogmios
  • Latest reply from SteveAtty