…in use for my Percona Server 5.6.10 sandbox: description=MySQL driver=com.mysql.jdbc.Driver connectionSpec=jdbc:mysql…number of children, parents, count of columns, row counts, and comments — a great way for a…in on a particular table Constraints – lists the explicit Foreign Key constraints in…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
…MySQL transaction descriptors optimization introduced in Percona Server 5.5.30-30.2 and a followup by Dimitri Kravchuk, we have received a large number…list when creating read views. However, the more general descriptors optimization in Percona Server showed fairly close results in our tests. In…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 20 Comments
…In practice, this means that it takes a minimum of a few seconds to incrementally refresh a view, even when the number…a quick example of the list of tables used by the above view, as stored in the data dictionary: mysql…
Post: Using Flexviews - part two, change data capture
March 25, 2011 By 26 Comments
…a demonstration of the utility. As a reminder, the first post covered the following topics: What is a materialized view…in a moment. Lets create a table, insert some rows, add a change log, delete rows and then insert some more of them: mysql… adding a table to the list …if you have a small number of …
Post: MySQL EXPLAIN limits and errors.
July 24, 2006 By 6 Comments
… a lot you probably noticed it is not always provide adequate information. Here is list…number of rows estimated from each row in a join and multiply them to see how many rows will be examined in…an alternative view. If you want to find more information about understanding EXPLAIN output, MySQL manual…
Post: Checking the subset sum set problem with set processing
May 16, 2011 By Leave a Comment
… the cardinality of each item in the input set). Notice that I have a lot of numbers in my list: mysql> select val, count(*) from data… | <-- now the check passes +-----+----------+ 5 rows in set (40.01 sec) Of course, I can use a materialized view and check the expression in subsecond.
Post: Data mart or data warehouse?
July 15, 2010 By 14 Comments
…lists of customers or products. Because of the partially denormalized nature of a star schema, the dimension tables in a…a large number of joins when many dimensions are involved. A…views. These features make working with a star schema much easier than it may be on MySQL…
Post: Percona XtraDB Cluster: Failure Scenarios with only 2 nodes
July 25, 2012 By 6 Comments
…rows in set (0.00 sec) percona2 mysql> select * from percona; +—-+—————+——–+ | id | inserted_from | name | +—-+—————+——–+ | 2 | percona1 | lefred | | 3 | percona2 | kenny | +—-+—————+——–+ 2 rows in…
Post: Using MyISAM in production
June 17, 2006 By 36 Comments
…number of tables. I still have the same view…from a lot of…in mind. So here is my list of items you need to keep into account while using MyISAM tables. Recovery. MySQL…in-row fragmentation which means single row may be stored in many pieces. In extreme cases I’ve seen over 10 pieces in average per row…
Post: Full Text Search Webinar Questions Followup
August 24, 2012 By 5 Comments
…a good idea to retrieve the same number of rows on each benchmark (I noticed 100 rows…to the MySQL database …list indexes, but not full-text indexes, so comparisons would not be meaningful. Since MemSQL is an in…viewed my Full-Text Search Throwdown webinar when I present the popular Percona Training in…
