…in MySQL 5.0. There are number of ways the problem can be solved but first we decide to see how…tables. It turned out one of the float columns stored “-0″ in MySQL 5.0 but it was displayed as “0″ when data loaded to…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 28 Comments
…another fact from…data isn’t in…to you, etc) and choose an amount of memory based on how important those tables are to you, how…in MySQL to guide your decisions. It is also not the be-all and end-all of MySQL…
Post: Recovering CREATE TABLE statement from .frm file
December 17, 2008 By 5 Comments
…in the Innodb tablespace from which we have to get data from…data files but have forgotten to delete the corresponding .frm files of InnoDB tables, or you have moved .frm files to another database? or, the table…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…in how to properly build the server to…to think of any harm that may happen here due to the way this variable is used. Moving on. ==9090== Possible data…table_state) (sql_show.cc:6238) ==9090== by 0x6A5E0C: JOIN::exec() (sql_select.cc:1863) ==9090== by 0x6A7D72: mysql_select(THD*, Item***, TABLE…
Post: Finding your MySQL High-Availability solution – Replication
November 13, 2009 By 6 Comments
…MySQL, altering a table means recreating the whole table and it is a blocking operations. Altering a large table…from writes Supports MyISAM Can lose data…MySQL servers lags behind too much, its read VIP will be moved to another server. As a conclusion, replication can be used in many cases to…
Post: Finding your MySQL High-Availability solution – The questions
October 16, 2009 By 36 Comments
…move on! How to determine which MySQL High-Availability solution is best? What is really tricky with MySQL is the number of possible HA solutions. From…another search engine like Sphinx in order to…
Post: MySQL Blob Compression performance benefits
January 11, 2008 By 17 Comments
…in the table it often makes sense to keep it compressed. Unfortunately MySQL does not provide compressed BLOB/TEXT columns (I would really love to…data from TEXT column you should pick BLOB type for compressed data storage. Before going ahead with compression I usually run some checks to…
Post: A case for MariaDB's Hash Joins
May 31, 2012 By Leave a Comment
…in the number of rows needed to be joined from supplier table (left operand). Test Case D – Join a large data set (>1M rows) from one table…table orders in PK order has another benefit that it implies reading the table lineitem in PK order. Hence, these benefits mean MySQL…
Post: Economics of Performance Optimization
March 13, 2008 By 9 Comments
…in the end. As project moves to the higher end another…to do inhouse consulting helping various projects to get things right. Both Google and Yahoo for example have great experts in MySQL and Scaling in…
Post: Estimating Replication Capacity
July 20, 2010 By 4 Comments
…in sharded environment you may need to schedule downtime or set object read only to move it to another…in Oracle MySQL Server. set userstat_running=1 and run following query: mysql> select * from information_schema.user_statistics where user=”#mysql…
