June 20, 2013

Post: Impact of the number of idle connections in MySQL

…. This script uses a PHP script, make_conn.php, to generate the idle connections. This script is the following: Before each…_mysql.sh” script to allow more processing threads (100) instead of the max of 20. This is required for another series of… not slowed down by handling all those connections. I tried generating the idle connections from a third box and the results…

Post: High availability for MySQL on Amazon EC2 – Part 2 - Setting up the initial instances

… file must be identical and good way to generate unique one is to run “date | md5sum” and …: root@hamysql:~# apt-get install mysql-server-5.1 The package install MySQL has an automatic startup script … is not the main purpose of this blog series. EBS based AMI Others have produce excellent article …

Post: InnoDB Full-text Search in MySQL 5.6 (part 1)

… it, and then I create one, the following warning is generated: mysql> alter table dir_test_innodb ADD FULLTEXT KEY (full_name… the underlying table, or it can be a sequence value generated by InnoDB when the table does not contain a suitable… nontrivial number of code changes. In part 2 of this series, we’ll reload and reset our SEO and DIR data…

Post: MySQL performance on EC2/EBS versus RDS

… I started a series of posts showing benchmark results on Amazon EC2 servers with RAID’ed EBS volumes and MySQL, versus RDS… overview of these two approaches to hosting MySQL in the Amazon cloud. In general, MySQL performance overall on EC2 and EBS isn… of I/O activity you’re generating, whichever comes first. And you could find that you generate more I/O than you…

Post: Data mart or data warehouse?

… part two in my six part series on business intelligence, with a focus on OLAP analysis….the kind of SQL which a ROLAP tool must generate to answer those queries. Performance challenges with larger databases,…easier than it may be on MySQL, but it is definitely possibly to use MySQL as long as the …

Post: Flexviews - part 3 - improving query performance using materialized views

…In my first post in this series, I described materialized views (MVs). An …the dictionary The following SQL is dynamically generated by the flexviews.get_sql() function …155187034 | <-- too high +------------------+ 1 row in set (0.68 sec) mysql> select sum(total_lines) from dashboard_customer_sales ;…

Post: Using Flexviews - part one, introduction to materialized views

… the first in a multi-part series describing Flexviews. Update: This series has a part 2 and part…too is the output of a SQL statement. MySQL even includes a SQL statement that makes this…compared to computing the results. You can often generate multiple different blocks of content from the summarized…

Comment: Star Schema Bechmark: InfoBright, InfiniDB and LucidDB

…s TPC-H legacy, including the randomized data generation. But it also appears to offer some nice…going up as you progress from Q1 series to Q4 series. In addition there is an Aggregation/…of 1465 seconds). http://infinidb.org/infinidb-blog/mysql-parallel-query-processing-of-ssb-queries-via-infinidb…

Post: Intro to OLAP

… first of a series of posts about business intelligence tools, particularly OLAP (or online analytical processing) tools using MySQL and other free… and the kind of SQL which a ROLAP tool must generate to answer those queries. Performance challenges with larger databases, and… the performance of OLAP with and without aggregation over multiple MySQL storage engines at various data scales. What is BI? Chances…

Post: Recovering Innodb table Corruption

…(index)) InnoDB: We intentionally generate a memory trap. InnoDB: Submit a detailed bug report to http://bugs.mysql.com. InnoDB: If you… place and as MySQL crashes it does not store all data it could recover to MyISAM table. Using series of queries with LIMIT can be handly if you recover manually: mysql> insert ignore into test2…