In a MySQL 5.7 master-slave setup that uses the default semisynchronous replication setting for rpl_semi_sync_master_wait_point, a crash of the master and failover to the slave is considered to be lossless. However, when the crashed master comes back, you may find that it has transactions that are not present in the current master (which was previously a slave). This behavior may be puzzling, given that semisynchronous replication is supposed to be lossless, but this is actually an expected behavior in MySQL. Why exactly this happens is explained in full detail in the …

By having appropriate indexes on your MySQL tables, you can greatly enhance the performance of SELECT queries. But, did you know that adding indexes to your tables in itself is an expensive operation, and may take a long time to complete depending on the size of your tables? During this time, you are also likely to experience a degraded performance of queries as your system resources are busy in index-creation work as well. In this blog post, we discuss an approach to optimize the MySQL index creation process in such a way that your regular workload is not impacted.

MySQL Rolling Index Creation

We call this approach a ‘Rolling Index Creation’ - if you have a MySQL master-slave replica set, you can create the index one node at a time in a rolling fashion. You should create the index only on the slave nodes so the master’s …

Introduction In this article, we are going to see how a deadlock can occur in a relational database system, and how Oracle, SQL Server, PostgreSQL, or MySQL recover from a deadlock situation. Database locking Relational database systems use various locks to guarantee transaction ACID properties. For instance, no matter what relational database system you are using, locks will always be acquired when modifying (e.g., UPDATE or DELETE) a certain table record. Without locking a row that was modified by a currently running transaction, Atomicity would be compromised. Using locking for controlling access... Read More

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AWS is the #1 cloud provider for open-source database hosting, and the go-to cloud for MySQL deployments. As organizations continue to migrate to the cloud, it’s important to get in front of performance issues, such as high latency, low throughput, and replication lag with higher distances between your users and cloud infrastructure. While many AWS users default to their managed database solution, Amazon RDS, there are alternatives available that can improve your MySQL performance on AWS through advanced customization options and unlimited EC2 instance type support. ScaleGrid offers a compelling alternative to hosting MySQL on AWS that offers better performance, more control, and no cloud vendor lock-in and the same price as Amazon RDS. In this post, we compare the performance of MySQL Amazon RDS …

Business-Critical MySQL using open source is free, right?

Managed MySQL cloud services do not need database administrators, correct?

Well…

Think again – and watch the replay of this webinar with our partner Datavail hosted by Database Trends & Applications on whether free is good enough for business-critical MySQL database environments.

Listen in as Srinivasa Krishna, MySQL Practice Leader at Datavail, and Eero Teerikorpi, CEO & Founder at Continuent discuss the pros and cons of the DIY approach vs getting professional help in.

…

Introduction Ever wanted to connect to a relational database using Java and didn’t know which JDBC Driver Maven dependency to use? If so, this article is surely going to help you from now on. Oracle Since September 2019, the Oracle JDBC Driver is available on Maven Central. For JDK 10 and 11, use the following Maven dependency: For JDK 8, use the ojdbc8 artifact instead: For more details about the proper version to use, check out the following Maven Central link. MySQL The MySQL Driver is available on Maven Central, so just... Read More

The post JDBC Driver Maven dependency list appeared first on Vlad Mihalcea.

In the last few years there have been several examples of major service problems affecting businesses data: outages causing data inconsistencies; unavailability or data loss, and worldwide cyberattacks encrypting your files and asking for a ransom.

Database-related incidents are a very common industry issue- even if the root cause is not the database system itself. No matter if your main relational system is MySQL, MariaDB, PostgresQL or AWS Aurora -there will be a time where you will need to make use of backups to recover to a previous state. And when that happens it will be the worst time to realize that your backup system hadn’t been working for months, or testing for the first time a cluster-wide recovery.

Forget about the backups, it is all about recovery!

Let me be 100% clear: the question is not IF data …

Up to now, the way of updating dbdeployer was the same as installing it for the first time, i.e. looking at the releases page, downloading the binaries for your operating system, unpacking it and finally replacing the existing binaries.

This is not the procedure I follow, however, as for me updating means just compile the latest version I have just finished coding. For this reason, when Simon Mudd mentioned to me that dbdeployer should update itself over the Internet, I didn’t immediately grasp the concept. But then he talked to me again, and he even coded a sample script that does what he …

WordPress is the largest website builder platform in the world, supporting over 34% of all websites on the internet today. MySQL is a free open source relational database management system that is leveraged across a majority of WordPress sites, and allows you to query your data such as posts, pages, images, user profiles, and more. As any WordPress developer knows, each installation requires a database in the backend, and MySQL is the database of choice for storing and retrieving your WordPress data.

In order for your WordPress website to be able to access, store and retrieve the data in your MySQL database, it needs to be hosted online through a cloud computing service. ScaleGrid offers a convenient way to setup and configure MySQL hosting for your …

Are you looking to get started with the world’s most popular open-source database, and wondering how you should setup your MySQL hosting? So many default to Amazon RDS, when MySQL performs exceptionally well on Azure Cloud. While Microsoft Azure does offer a managed solution, Azure Database, the solution has some major limitations you should know about before migrating your MySQL deployments. In this post, we outline the best way to host MySQL on Azure, including managed solutions, instance types, high availability replication, backup, and disk types to use to optimize your cloud database performance.

MySQL DBaaS vs. Self-Managed MySQL

The first thing to consider when weighing between self-management and a MySQL Database-as-a-Service …