(Ovais Tariq) I have been working with a few customer cases and one interesting case popped up. The customer was facing a peculiar problem where the rows column in the EXPLAIN output of the query was totally off. The actual number of rows was 18 times more than the number of rows reported by MySQL i
Tag: Open Source
TIL: Lookout For DEFINER
(Gerry Narvaja) I haven’t blogged in a while an I have a long TODO list of things to publish: The repository for the SNMP Agent, video and slides of my OSCON talk and a quick overview of MHA master-master support. In the meantime, here’s a little fact that I didn’t know from MySQL CREATE VIEW docume
Uh, uh… who caused that error? MySQL ?!
(Ulf Wendel) Support nightmare: a customer reports a random PHP MySQL error. As a support expert you have the strong feeling that it is down to some suspicious SQL sequence. How to proof? 25 lines of PECL/mysqlnd_uh swiss-army knife magic…
Improving speed of GIST indexes in PostgreSQL 9.2
(Leo Hsu and Regina Obe) This is about improvements to GIST indexes that I hope to see in PostgreSQL 9.2. One is a patch for possible inclusion in PostgreSQL 9.2 called SP-GiST, Space-Partitioned GiST created by Teodor Sigaev and Oleg Bartunov whose basic technique is described in SP-GiST: An Extens
Uh, uh… extending mysqlnd: monitoring and statement redirection
(Ulf Wendel) Uh, uh… about a year ago Mayflower OpenSource Labs released the mysqlnd user handler plugin (PECL/mysqlnd_uh). The extension lets you extend and replace mysqlnd internal function calls with PHP.
Why are your indexes larger than your actual data?
(Jonathan Levin) I sometimes encounter this phenomenon when a database has tables in which the indexes are larger—sometimes much larger—than the actual data stored in the table.
Uh, uh… extending mysqlnd: monitoring and statement redirection
(Ulf Wendel) Uh, uh… about a year ago Mayflower OpenSource Labs released the mysqlnd user handler plugin (PECL/mysqlnd_uh). The extension lets you extend and replace mysqlnd internal function calls with PHP.
Infinite Replication Loop
(Frederic Descamps) Last week I helped 2 different customers with infinite replication loops. I decided to write a blog post about these infinite loop of binary log statements in MySQL Replication. To explain what they are, how to identify them… and how to fix them.
Change Views DEFINER without ALTER VIEW : how to fix thousands of views!
(Rene Cannao) Recently I faced an interesting challenge: modify over 26k views on a single mysqld instance.
Optimizer tracing: Query Execution Plan descriptions beyond EXPLAIN
(Jørgen Løland) Understanding why MySQL chooses a particular join order or why table scan is chosen instead of range scan is often very hard even for experienced MySQL users. Two almost identical queries, differing only in constant values, may produce completely different plans.
