… the server is not heavily loaded, I may even do some INFORMATION_SCHEMA queries to help me find the biggest tables and so forth. If the… default, this outputs the top 10 most expensive queries, in total execution time. By the way, the slow query logs in the stock MySQL server are extremely…
Post: Researching your MySQL table sizes
March 17, 2008 By 28 Comments
…56 sec) Find the same data using some filter I often use similar queries to find space… | +——–+———+———+——-+————+———+ 1 row in set (0.03 sec) Find biggest databases SELECT count(*) tables, table_schema… | 0.00G | 0.00G | 0.72 | | 17 | mysql | 0.00M | 0.00G | 0.00G | 0…
Post: Fishing with dynamite, brought to you by the randgen and dbqp
November 16, 2011 By Leave a Comment
…the gamble is that this effort will produce more interesting effects on the database than the hand-written queries…the biggest difficulties in fixing bugs comes from being able to recreate them reliably and easily. Between the…
Post: Data mart or data warehouse?
July 15, 2010 By 14 Comments
…jobs is often one of the biggest parts of designing and …tables (item_category,category) to find the category. These are not…MySQL, but it is definitely possibly to use MySQL as long as the…the multi-dimensional query language. Mondrian turns MDX into SQL, so we’ll also look at the kinds of queries…
Post: Goal driven performance optimization
December 22, 2008 By Leave a Comment
… more practical to look from the top of the stack. If you look at MySQL log you may find some queries which are slow but… do is to run the query to see what are contributing factors to the response time of the problematic pages: mysql> select count(*),avg(wtime… case this portion is not the biggest part yet but if we’d speed up Sphinx and MySQL dramatically we would have to…
Post: To pack or not to pack - MyISAM Key compression
May 13, 2006 By 4 Comments
… MySQL will need to scan keyblock from the start uncompressing keys to find matching key value. This means the…hack 
The fact MyISAM will by default compress string keys but not integer keys is the biggest reason …some benchmarks. I’m testing 4 types of queries: select count(*) from t1, t1 t2 where …
Post: Sell-an-Elephant-to-your-Boss-HOWTO
August 28, 2012 By 3 Comments
…the identification of performance problems that takes most of the time. Nor it is looking for the right solution. Biggest bottleneck in the…queries, tuning MySQL etc. which we can offload 80-90% from the team. On the other hand, if the…
