Last_SQL_Error: Could not execute <Update/insert/delete>_rows event on table <dbname>.<tablename>; Can’t find record in ‘<tablename>’, Error_code: 1032; handler error HA_ERR_END_OF_FILE; the event’s master log <master binary log file name>, end_log_pos <master log file position>

This is one of the error for MySQL Replication when MASTER and SLAVE replica not in sync. The Reason for replication getting out of sync due to various reasons. But the common cause is particular table row or data not matched/missing on the slave while applying transaction received from MASTER. This transaction can be insert/update/delete type.

In this blog post will discuss support for MEMORY storage engine table with MySQL Replication and few examples with a possible solution. As per official MySQL DOC, …

In Amazon space, any EC2 or Service instance can “disappear” at any time.  Depending on which service is affected, the service will be automatically restarted.  In EC2 you can choose whether an interrupted instance will be restarted, or left shutdown.

For an Aurora instance, an interrupted instance is always restarted. Makes sense.

The restart timing, and other consequences during the process, are noted in our post on Aurora Failovers.

Aurora Testing Limitations

As mentioned earlier, we love testing “uncontrolled” failovers.  That is, we want to be able to pull any plug on any service, and see that the environment as a whole continues to do its job.  We can’t do that with Aurora, because we can’t control the essentials:

• power button;
• reset switch;
…

How it happened

A few years ago I started thinking about refactoring MySQL-Sandbox. I got lots of ideas and a name for the project (dbdeployer) but went no further. The initial idea (this was 2013!) was to rewrite the project in Ruby: I had been using Ruby at work and it looked like a decent replacement for Perl. My main problem was the difficulty of installation in an uncontrolled environment. If you have control over your environment (it's your laptop or you are in charge of the server configuration via Puppet or similar) then the task is easy. But if you ever need to deploy somewhere with little or no notice, it becomes a problem: there are servers where Perl is not installed, and is common that the server also have a policy forbidding all scripting languages from being deployed. …

Right now Aurora only allows a single master, with up to 15 read-only replicas.

Master/Replica Failover

We love testing failure scenarios, however our options for such tests with Aurora are limited (we might get back to that later).  Anyhow, we told the system, through the RDS Aurora dashboard, to do a failover. These were our observations:

Role Change Method

Both master and replica instances are actually restarted (the MySQL uptime resets to 0).

This is quite unusual these days, we can do a fully controlled role change in classic asynchronous replication without a restart (CHANGE MASTER TO …), and Galera doesn’t have read/write roles as such (all instances are technically writers) so it doesn’t need role changes at all.

Failover Timing

Failover between running instances takes about 30 seconds.  This is in line with information provided in the …

Our clients operate on a variety of platforms, and RDS (Amazon Relational Database Service) Aurora has received quite a bit of attention in recent times. On behalf of our clients, we look beyond the marketing, and see what the technical architecture actually delivers.  We will address specific topics in individual posts, this time checking out what the Aurora architecture means for write and caching behaviour (and thus performance).

What is RDS Aurora?

First of all, let’s declare the baseline.  MySQL Aurora is not a completely new RDBMS. It comprises a set of Amazon modifications on top of stock Oracle MySQL 5.6 and 5.7, implementing a different replication mechanism and some other changes/additions.  While we have some information (for instance from the “deep dive” by AWS VP Anurag Gupta), the source code of the Aurora modifications …

In this blog post, I will talk about archiving MySQL tables in ClickHouse for storage and analytics.

Why Archive?

Hard drives are cheap nowadays, but storing lots of data in MySQL is not practical and can cause all sorts of performance bottlenecks. To name just a few issues:

1. The larger the table and index, the slower the performance of all operations (both writes and reads)
2. Backup and restore for terabytes of data is more challenging, and if we need to have redundancy (replication slave, clustering, etc.) we will have to store all the data N times

The answer is archiving old data. Archiving does not necessarily mean that the data will be permanently removed. Instead, the archived data can be placed into long-term storage (i.e., AWS S3) or loaded into a …

At Mydbops we always thrive to provide the best MySQL Solutions. We are exploring the modern SQL load balancers. We have planned to write a series of blog on ProxySQL.

The first blog in this series is  how to set up ProxySQL for MySQL Replication Topology including Read / Write Split and some background over ProxySQL.

What is ProxySQL ?

• ProxySQL is a open-source high-performance SQL aware proxy. It runs as a daemon watched by a monitoring process.
• ProxySQL seats between application and db servers.
• The daemon accepts incoming traffic from MySQL clients and forwards it to backend MySQL servers.

A few most commonly used features are : …

Since January 2017, the MySQL Replication Team has been involved in processing many Community Contributions !

We are really happy to receive contributions (and not only in the replication team), but this also implies a lot of work from our engineers, as more than resolving a bug or developing a new feature, code contributions need to be analyzed, the code needs to be understood and validated.…

Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

Percona Live Santa Clara 2018 update: tutorials have been announced. The committee rated over 300+ talks, and easily 70% of the schedule should go live next week as well. In practice, then, you should see about 50 talks announced next week. There’s been great competition: we only have 70 slots in total, so about 1 in 5 talks get picked — talk about a competitive ratio.

FOSDEM

FOSDEM was truly awesome last week. From a Percona standpoint, we had a lot of excellent booth traffic (being outside of the PostgreSQL room on Saturday, and not too far out from the MySQL room on Sunday). We gave away bottle openers — …

Welcome to the January 2018 Continuent Product Management newsletter. It’s the start of the year, and so a good opportunity to look forward, as well as back a little to see how we did. Let’s start with the immediate future first.

• Tungsten Clustering 6.0 is Coming!
• Tungsten Replicator 6.0 is Also Coming!
• Looking at the Year Ahead
• Tungsten Backup, Tungsten Connector
• Tungsten GUI
• End-of-Life Policy
• Release Schedule
• Internal Tweaks

Tungsten Clustering 6.0 is Coming!

The development and restructuring of the product has taken a year to come to fruition, as there are quite a lot of different components, but the new version of Tungsten Clustering 6.0 is due out in February and we’re really pleased with the result.

The focus of this release of the product is to unify the components that previously …