The use of open source databases has increased steadily in recent years. Past trepidation — about perceived vulnerabilities and performance issues — has faded as decision makers realize what an “open source database” really is and what it offers. This comprehensive overview examines open source database architecture, types, pros and cons, uses by industry, and how open source databases compare with proprietary databases. This guide also covers key factors to consider when selecting the right open source database for your organization. 1. What is an open source database? In simple terms, an op ..read more

Compression in any database is necessary as it has many advantages, like storage reduction, data transmission time, etc. Storage reduction alone results in significant cost savings, and we can save more data in the same space. As the amount of data grows, the need for efficient data compression becomes increasingly important to save storage space, reduce I/O overhead, and improve query performance. In this blog, we will discuss both data and network-level compression offered in MongoDB. We will discuss snappy and zstd for data block and zstd compression in a network. Percona Server for MongoD ..read more

A partitioned table in MySQL has its data separated into different tablespaces while still being viewed as a single table. Partitioning can be a useful approach in some cases when handling huge sets of data. Deleting huge data sets could be quickened up in a partitioned table, but if not handled properly, it can misplace your data in the table. In this blog, I will share how to check and fix the data in such a table with minimal disruption to the table. In this example, we use a table partitioned based on a date range. mysql> show create table salariesG *************************** 1. row ..read more

In this blog post, we will dive deep into WiredTiger’s Logging and Checkpoint mechanism. Every database system has to ensure durability and reliability. MongoDB uses classic Write-Ahead-Logging (WAL) using Journals and Checkpoints. Starting with the basics, why is WAL needed in the first place? It’s to ensure that our data is durable after each write operation and to make it persistent and consistent without compromising the performance. In terms of MongoDB, it achieves WAL and data durability using a combination of both Journaling and Checkpoints. Let’s understand both of them. 1. Journal It ..read more

Our previous blogs discussed configuring and setting up backups using the pgBackRest solution. To briefly explain pgBackRest, it is an open source backup tool that takes FULL Backup, Incremental Backup, and Differential Backup for PostgreSQL databases. Repository means the location/path on the server or the cloud where the actual copy of the backup will reside. In this blog, we will specifically discuss one of the important features of the pgBackRest called Multiple Repository (or, in short, Multi Repo). This attribute helps take the redundant copies of the databases at multiple locations rem ..read more

‘E11000 duplicate key error’ is an error that you might have encountered during the restore process. In this blog, we will talk about in what scenario you might face this error when restoring Oplog for PITR (point-in-time recovery). You might wonder why this error will come during PITR as the operations in the Oplog are idempotent, meaning they always result in the same change to the database no matter how many times they’re performed. Now let’s see in which scenario you might face this error while applying Oplog. I created a collection book with four documents with a unique compound index. S ..read more

On MySQL and Percona Server for MySQL, there is a schema called information_schema (I_S) which provides information about database tables, views, indexes, and more. A lot of useful information can be retrieved from this schema, for example, table metadata and foreign key relations, but trying to query I_S can induce performance degradation if your server is under heavy load, as shown in the following example test. Disclaimer: This blog post is meant to show a less-known problem but is not meant to be a serious benchmark. The percentage in degradation will vary depending on many factors {hardw ..read more

It’s time for the release roundup! Percona is a leading provider of unbiased open source database solutions that allow organizations to easily, securely, and affordably maintain business agility, minimize risks, and stay competitive. Our Release Roundups showcase the latest Percona software updates, tools, and features to help you manage and deploy our software. It offers highlights, critical information, links to the full release notes, and direct links to the software or service itself to download. Today’s post includes those releases and updates that have come out since March 13, 2023. Take ..read more

In MySQL Server 8.0.32, Oracle fixed Bug #105761: “mysqldump make a non-consistent backup with ‐‐single-transaction option” (this commit) which caused a wave of complaints from users who could no longer do backups with the mysqldump utility because of the lack of the required privileges. Bug #109701 “Fix for #33630199 in 8.0.32 introduces regression when ‐‐set-gtid-purged=OFF” Bug #109685 “mysqldump has incompatible change in MySQL 8.0.32″ Later, Oracle admitted the problem and even added a new paragraph to the MySQL Server 8.0.32 Release Notes. Limitation: This fix adds a requirement for ..read more

You might want to use binlog compression with MySQL/Percona Server for MySQL, but it can come with drawbacks. This article discusses the need for using binlog compression and the potential issues it may cause. Binlog compression is a technique used to reduce the size of binary log files, which can become quite large over time. This can be especially important in situations where disk space is limited. However, it’s important to be aware that using binlog compression can also cause issues with replication. Consider the following scenario: you have restored a backup that was taken from a replic ..read more