MySQL
The GRANT/REVOKE dilemma
It is common practice to grant your application the privileges of “GRANT SELECT, INSERT, UPDATE, DELETE ON yourdb.* TO user@host”. But what if you want to ensure you cannot DELETE data from just one table?
Read moreUnexplained halts using mysql command line client
I recently came across an issue trying to connect to a MySQL server using the mysql client. It appeared as through the connection was hanging. A subsequent connection using the -A option highlighted the problem with the previous connection stuck in the state “Waiting for table metadata lock”.
Read moreGiving thanks to MySQL authors challenge
Next week the US celebrates Thanksgiving Day. For those that are American or live here, this is a significant event. Three different experiences recently have lead me to write this request for ALL MySQL community members to give thanks to those that have contributed to the MySQL ecosystem.
Read moreKick all the tires before you buy the product
Translating theory to practice is never easy. Morgan gives us the right steps in a play environment to move from dev.mysql.com native MySQL rpm’s to the new MySQL yum repository. I thought I would try it out.
Read moreWhat SQL is running in MySQL
Using the MySQL 5.6 Performance Schema it is very easy to see what is actually running on your MySQL instance. No more sampling or installing software or worrying about disk I/O performance with techniques like SHOW PROCESSLIST, enabling the general query log or sniffing the TCP/IP stack.
Read moreMonitoring an online MySQL ALTER TABLE using Performance Schema
Recently a client asked me how long it would take for an ALTER TABLE to complete. Generally the answer is “it depends”. While this was running on a production system I tried with the Performance Schema in MySQL 5.
Read moreMySQL shutdown via service reporting ERROR
Working with MySQL 5.6 under CentOS 6.4 I came across the following problem with MySQL reporting it did not shutdown successfully. $ sudo su - $ service mysql stop Shutting down MySQL.
Read moreUpdating MySQL using official repositories
The announcement of the MySQL Yum repositories was a long overdue request on my wish list. While it was possible to find MySQL at http://public-yum.oracle.com/ it was not the GA version MySQL 5.
Read moreMySQL performance schema threads
A trap for those new to the MySQL Performance Schema is the expectation that thread_id in tables such as events_statements_current matches the id you find in the MySQL processlist. This is NOT TRUE.
Read moreWhat causes LOST_EVENTS error in the MySQL binary log?
Using MySQL 5.6.13 under CentOS 6.4, I had a replication failure on one master/slave topology because the master binary log had the following entry that was intentionally written by the MySQL server.
Read moreMySQL/NoSQL/Cloud Conference Latin America
Last week I was a guest speaker at the second annual MySQL/NoSQL/Cloud Conference held in Buenos Aires, Argentina. Thanks to Santiago Lertora from Binlogic who has taken on the responsibility of organizing a event for the MySQL community in South America.
Read moreAn unexplained connection experience
The “Too many connections” problem is a common issue with applications using excessive permissions (and those that grant said global permissions). MySQL will always grant a user with SUPER privileges access to a DB to investigate the problem with a SHOW PROCESSLIST and where you can check the limits.
Read moreA friday MongoDB funny
I had to laugh (just a bit) at this on the exhibitor floor at Oracle Open World 2013. There was a large MongoDB presence at the Slot 301 . There are a few reasons.
Read moreAdditional DB objects in AWS RDS
To expand on Jervin’s Default RDS Account Privileges , RDS for MySQL provides a number of routines and triggers defined the the ‘mysql’ meta schema. These help in various tasks because the SUPER privilege is not provided.
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