Featured
Percona Products
Percona Services
Use Cases
Sveta SmirnovaIt is a common use case to synchronize data in two tables inside MySQL servers. This blog post describes one specific case: how to synchronize data between two different tables on the same MySQL server. This could be useful, for example, if you test DML query performance and do not want to affect production data. […]
“It would be nice to have an option, that would allow to suppress the DEFINER statement in the CREATE VIEW statements generated by mysqldump. This would help when transferring data structures between databases with different security models.” TLDR; Use mysqlpump with option --skip-definer instead of mysqldump. The Story This was requested as MySQL Bug #24680 on […]
Apologies for the silly title, but the issue is a real one, even though it is not a new thing. Schema upgrades are not an ordinary operation in Galera. For the subject at hand, the bottom line is: under the default Total Order Isolation (TOI) method, “the cluster replicates the schema change query as a […]
Recovering to a particular time in the past is called Point-In-Time Recovery (PITR). With PITR you can rollback unwanted DELETE without WHERE clause or any other harmful command. PITR with Percona XtraBackup is pretty straightforward and perfectly described in the user manual. You need to restore the data from the backup, then apply all binary […]
I got this question on the “How to Avoid Pitfalls in Schema Upgrade with Percona XtraDB Cluster (PXC)” webinar and wanted to answer it in a separate post. Will RSU have an effect on GTID consistency if replication PXC cluster to another cluster? Answer for this: yes and no. Galera assigns its own GTID for […]
First I want to thank everyone who attended my May 21, 2020 webinar “How Safe is Asynchronous Master-Master Setup in MySQL?“. Recording and slides are available on the webinar page. Here are answers to the questions from participants which I was not able to provide during the webinar. Q: What do you generally think of […]
March is not only the month when a pandemic closed all borders and people had to stay home on the quarantine; it’s also the month when daylight saving time change happens. For some regions, this is not only a time change but also a switch to a different timezone. For example, New York uses EST […]
First I want to thank everyone who attended my December 19, 2019 webinar “Top 3 Features of MySQL“. Recording and slides are available on the webinar page. Here are answers to the questions from participants which I was not able to provide during the webinar. Q: When do undo logs and redo logs come into […]
First I want to thank everyone who attended my December 5, 2019 webinar “Introduction to MySQL Query Tuning for DevOps“. Recording and slides are available on the webinar page. Here are answers to the questions from participants which I was not able to provide during the webinar. Q: How to find stored execution plans and […]
Less than one month left until Percona Live. This time the Committee work was a bit unusual. Instead of having one big committee for the whole conference we had a few mini-committees, each responsible for a track. Each independent mini-committee, in turn, had a leader who was responsible for the whole process. I led the […]
When users experience memory usage issues with any software, including MySQL®, their first response is to think that it’s a symptom of a memory leak. As this story will show, this is not always the case. This story is about a bug. All Percona Support customers are eligible for bug fixes, but their options vary. […]
Please join Percona’s Principal Support Engineer Sveta Smirnova as she presents Billion Goods in Few Categories: How Histograms Save a Life? Watch the Recorded Webinar We store data with the intention to use it: search, retrieve, group, sort, etc. To perform these actions effectively, MySQL storage engines index data and communicate statistics with the Optimizer […]
Please join Percona’s Principal Support Engineer, Sveta Smirnova, as she presents MySQL Performance Schema in 1 hour on Thursday, March 21st, 2019, at 10:00 am PDT (UTC-7) / 1:00 pm EDT (UTC-4). View the Recording MySQL 8.0 Performance Schema is a mature tool, used by humans and monitoring products. It was born in 2010 as […]
Just about a month ago, Pavel Ivanov released Ripple under the Apache-2.0 license. Ripple is a MySQL binlog server: software which receives binary logs from MySQL or MariaDB servers and delivers them to another MySQL or MariaDB server. Practically ,this is an intermediary master which does not store any data, except the binary logs themselves, […]
Lately, I worked on several queries which started returning wrong results after upgrading MySQL Server to version 5.7 The reason for the failure was derived merge optimization which is one of the default optimizer_switch options. Issues were solved, though at the price of performance, when we turned it OFF . But, more importantly, we could not […]
Please join Percona’s Principal Support Escalation Specialist Sveta Smirnova as she presents Troubleshooting Best Practices: Monitoring the Production Database Without Killing Performance on Wednesday, June 27th at 11:00 AM PDT (UTC-7) / 2:00 PM EDT (UTC-4). Register Now During the MySQL Troubleshooting webinar series, I covered many monitoring and logging tools such as: General, slow, […]
If you attended my latest Troubleshooting MySQL Concurrency Issues with Load Testing Tools webinar you learned how I exploit benchmarking tools to replicate locking issues and crashes. But I told you nothing about proper use of these tools: for reliable benchmarks. I did not tell you that for a reason… I am just a Support […]
In this blog, I will provide answers to the Q & A for the Troubleshooting MySQL Concurrency Issues with Load Testing Tools webinar. First, I want to thank everybody for attending my May 23, 2018, webinar on troubleshooting tools for MySQL. The recording and slides for the webinar are available here. Below is the list […]
At my latest webinar “MySQL Test Framework (MTR) for Troubleshooting”, I received an interesting question about MTR test cases for Percona XtraDB Cluster (PXC). Particularly about testing SST and IST. This post is intended to answer this question. It assumes you are familiar with MTR and can write tests for MySQL servers. If you are […]
Please join Percona’s Principal Support Escalation Specialist, Sveta Smirnova, as she presents Troubleshooting MySQL Concurrency Issues with Load Testing Tools on Wednesday, May 23, 2018 at 11:00 AM PDT (UTC-7) / 2:00 PM EDT (UTC-4). Register Now Normally, we use benchmarking tools when we are developing applications. When applications are deployed, benchmarks tests are usually too […]