Percona Server release 11.0 which we announced few days ago unfortunately was released with a bug introduced while implementing stripping comments in query cache which could cause server crash with certain types of queries if query cache is enabled. We have released Percona Server release 11.1 which includes a fix for […]Read more
The problem I am going to describe is likely to be around since the very beginning of MySQL, however unless you carefully analyse and profile your queries, it might easily go unnoticed. I used it as one of the examples in our talk given at phpDay.it conference last week to demonstrate some pitfalls one […]Read more
Upgrading from MySQL 5.0 to MySQL 5.1 or Percona Server 5.1 you may run into issues with mysql_upgrade – it will identify some tables to be upgraded and will attempt to run REPAIR TABLE for them. This will fail with “The storage engine for the table doesn’t support repair” error […]Read more
As I wrote about 2 years ago the feature of Innodb to store copy of master’s position in Slave’s Innodb tablespace got broken. There is a lot of discussions at the corresponding bug report while outcome of the fix remained uncertain for me (the bug is market duplicate while the bugs […]Read more
There was a discussion on LinkedIn one month ago that caught my eye:
Database search by “within x number of miles” radius?
Anyone out there created a zipcode database and created a “search within x numer of miles” function ?
Thankful for any tips you can throw my way..
A few people commented that some solutions wouldn’t scale. […]Read more
I had an interesting case recently. The customer dealing with large MySQL data warehouse had the table which was had data merged into it with INSERT ON DUPLICATE KEY UPDATE statements. The performance was extremely slow. I turned out it is caused by hundreds of daily partitions […]Read more
Over last couple of years I have ran into random MySQL crashes in production when multiple key caches were used. Unfortunately this never was frequent or critical enough issue so I could spend time creating repeatable test case and search of the bug in the MySQL database did not find anything. […]Read more
Recently my attention was brought to this bug which is a nightmare bug for any consultant.
Working with production systems we assume reads are reads and if we’re just reading we can’t break anything. OK may be we can crash the server with some select query which runs into some bug but not […]
What bug makes you to recommend upgrading most frequently ? For me it is this bug which makes it quite painful to automate various replication tasks.
It is not the most critical bug by far but this makes it worse – critical bugs would usually cause upgrades already or were worked around while […]