Insight for DBAs

PostgreSQL Updatable Views: Performing Schema Updates With Minimal Downtime

postgres updatable views

Recently, one of our customers asked us how to minimize downtime when upgrading the database structure with changes that are not backwards-compatible. It’s an interesting question and I would like to visit some alternatives here. I will use PostgreSQL for this series of posts and walk through updatable views, INSTEAD OF Triggers, and the […]

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Upcoming Webinar Wed 1/9: Walkthrough of Percona Server MySQL 8.0

Walkthrough of Percona Server for MySQL 8.0

Please join Percona’s MySQL Product Manager, Tyler Duzan as he presents Walkthrough of Percona Server MySQL 8.0 on Wednesday, January 9th at 11:00 AM PDT (UTC-7) / 2:00 PM (UTC-4).
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Our Percona Server for MySQL 8.0 software is the company’s free, enhanced, drop-in replacement for MySQL Community Edition. The software includes all of the […]

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Amazon RDS Aurora MySQL – Differences Among Editions

differences MySQL aurora versions

Amazon Aurora with MySQL Compatibility comes in three editions which, at the time of writing, have quite a few differences around the features that they support.  Make sure you don’t assume the newer Aurora 2.x supports everything in Aurora 1.x. On the contrary, right now Aurora 1.x (MySQL 5.6 based) supports most Aurora features.  […]

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Upcoming Webinar Friday 1/4: High-Performance PostgreSQL, Tuning and Optimization Guide

High-Performance PostgreSQL, Tuning and Optimization Guide

Please join Percona’s Senior Software Engineer, Ibrar Ahmed as he presents his High-Performance PostgreSQL, Tuning and Optimization Guide on Friday, January, 4th, at 8:00 AM PDT (UTC-7) / 11:00 AM EDT (UTC-4).
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PostgreSQL is one of the leading open-source databases. Out of the box, the default PostgreSQL configuration is not tuned for any workload. […]

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MongoDB Backup: How and When To Use PSMDB hotbackup and mongodb_consistent_backup

mongodb backup

We have many backup methods to backup a MongoDB database using native mongodump or external tools. However, in this article, we’ll take a look at the backup tools offered by Percona, keeping in mind the restoration scenarios for MongoDB replicaSet and Sharded Cluster environments. We’ll explore how and when to use the tool mongodb-consistent-backup from […]

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MySQL 8 and The FRM Drop… How To Recover Table DDL

MySQL 8 frm drop recover ddl

… or what I should keep in mind in case of disaster

To retrieve and maintain in SQL format the definition of all tables in a database, is a best practice that we all should adopt. To have that under version control is also another best practice to keep in mind.
While doing that may seem […]

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Nondeterministic Functions in MySQL (i.e. rand) Can Surprise You

MySQL non deterministic functions rand

Working on a test case with sysbench, I encountered this:

MySQL

mysql> select * from sbtest1 where id = round(rand()*10000, 0);
+——+——–+————————————————————————————————————————-+————————————————————-+
| id | k | c […]

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MongoDB 4.0: Using ACID Multi-Document Transactions

mongodb 4.0 acid compliant transactions

MongoDB 4.0 is around, and there are a lot of new features and improvements. In this article we’re going to focus on the major feature which is, undoubtedly, the support for multi-document ACID transactions. This novelty for a NoSQL database could be seen as a way to get closer to the relational world. Well, […]

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PostgreSQL Streaming Physical Replication With Slots

postgres replication using slots

PostgreSQL streaming physical replication with slots simplifies setup and maintenance procedures. Usually, you should estimate disk usage for the Write Ahead Log (WAL) and provide appropriate limitation to the number of segments and setup of the WAL archive procedure. In this article, you will see how to use replication with slots and understand what problems […]

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