Introduction In this article, we are going to see how we can limit the SQL query result set to the Top-N rows only. Limiting the SQL result set is very important when the underlying query could end up fetching a very large number of records, which can have a significant impact on application performance. Why limit the number of rows of a SQL query? Fetching more data than necessary is the number one cause of data access performance issues. When a given business use case is developed, the amount of data available... Read More

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Introduction In this article, we are going to see how we can sort an SQL query result set using an ORDER BY clause that takes a RANDOM function provided by a database-specific function. This is a very handy trick, especially when you want to shuffle a given result set. Note that sorting a large result set using a RANDOM function might turn out to be very slow, so make sure you do that on small result sets. If you have to shuffle a large result set and limit it afterward, then it’s... Read More

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Ready to transition from a commercial database to open source, and want to know which databases are most popular in 2019? Wondering whether an on-premise vs. public cloud vs. hybrid cloud infrastructure is best for your database strategy? Or, considering adding a new database to your application and want to see which combinations are most popular? We found all the answers you need at the Percona Live event last month, and broke down the insights into the following free trends reports:

• Top Databases Used: Open Source vs. Commercial
• Cloud Infrastructure Analysis: Public Cloud vs. On-Premise vs. Hybrid Cloud
• Polyglot Persistence Trends: …

Kubernetes Operators are amazing and they are already playing an important role for those who are managing large scale applications. I personally think that we will manage all applications using Operators.

In this tutorial I will show you how to setup a MySQL cluster using the MySQL Operator on Kubernetes.

Prerequisites:

1. Install kubectl
2. Install Helm
3. Kubernetes Cluster: Use minikube locally or check out Luca’s post on how to set up OKE.

Let’s start with cloning the MySQL repository which contains the …

Introduction In this article, we are going to see how we can implement a database job queue using SKIP LOCKED. I decided to write this article while answering this Stack Overflow question asked by Rafael Winterhalter. Since SKIP LOCKED is a lesser-known SQL feature, it’s a good opportunity to show you how to use it and why you should employ it, especially when implementing a job queue task. Domain Model Let’s assume we have the following Post entity which has a status Enum property looking as follows: The PostStatus Enum encapsulates the... Read More

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Wondering which databases are trending in 2019? We asked hundreds of developers, engineers, software architects, dev teams, and IT leaders at DeveloperWeek to discover the current NoSQL vs. SQL usage, most popular databases, important metrics to track, and their most time-consuming database management tasks. Get the latest insights on MySQL, MongoDB, PostgreSQL, Redis, and many others to see which database management systems are most favored this year.

SQL vs. NoSQL

As any database administrator knows, the first question you have to ask yourself is whether to use a SQL or NoSQL database for your application. …

This log buffer edition overs cloud, Oracle, PostgreSQL and MySQL.

Cloud

On December 4, 2018 Microsoft’s Azure Database for Open Sources announced the general availability of MariaDB. This blog intends to share some guidance and best practices for alerting on the most commonly monitored metrics for the service.

Technology allows manufacturers to generate more data than traditional systems and users can digest. Predictive analytics, enabled by big data and cloud technologies, can take advantage of this data and provide new and unique insights into the health of manufacturing equipment and processes.

…

This year I participated for the first time to the DOAG, the conference which takes place in November in Nuremberg. Here some key words about this event: Oracle and other technologies, 2000 visitors, more than 400 sessions, more than 800 abstracts sent, exhibitors…
And for me everything started when in June I decided to send an abstract for a MySQL session.

Preparation

I’ve been working on MySQL for several years. At the beginning of this year, I started testing the new 8.0 version. We live in an age where security is more important than ever, GDPR and other regulations force us to review some subjects such as privacy and data policies. MySQL put in place lots of improvements regarding security in this last version.
So my session proposal for the DOAG was the following one:

MySQL 8.0 Community – Ready for GDPR ?
One of the most topical subject today is …

Considering the modern world of technology, where distributed system play a key role, replication in MySQL® is at the very heart of that change. It is very exciting to deliver this presentation and to be able to show everyone the greatest and the latest features that MySQL brings in order to continue the success that it has always been in the past.

The talk is suitable for anyone that’s interested in knowing what Oracle is doing with MySQL replication. Old acquaintances will get familiarized about new features already delivered and being considered and newcomers to the MySQL ecosystem will see how great MySQL Replication has grown to be and how it fits in their business..

What I’m most looking forward to at Percona Live Europe…

We are always eager to get feedback about the …

So, if we’re applying GDPR to our system, and we’re already making use of MySQL Transparent Data Encryption / keyring, then here’s an example on how to migrate from filed-based keyring to the encrypted keyring. Online.

If you’re looking to go deeper into the TDE then I suggest reading the MySQL Server Team’s InnoDB Transparent Tablespace Encryption blog.

You’d already have your environment running, whereas I have to create one.. give me a minute please, 8.0.12 here we come:

mysqld --defaults-file=my_okv.cnf --initialize-insecure --user=khollman
mysqld --defaults-file=my_okv.cnf --user=khollman &

mysql …