MinervaDB Blog: Mastering WebScale Database Infrastructure

MySQL 8 Metadata Locks: How Contention Was Reduced

MySQL 8 introduced several improvements to reduce contention for metadata locks, which are locks that are used to manage access to database objects such as tables and indexes. Here are a few ways in which […]

MySQL 8 Invisible Indexes: How They Work in Practice

In MySQL 8, invisible indexes are a feature that allows you to create an index without it being used by the optimizer. This can be useful in situations where you want to test the impact […]

PostgreSQL Hard Parsing: When Optimization Takes More Time

In PostgreSQL, hard parsing optimization typically takes more time when a query is submitted for the first time or when the database statistics or query planner configuration has changed significantly. This is because hard parsing […]

PostgreSQL Process Global Area: Tuning Guide

In PostgreSQL, the process global area (PGA) is managed by the server’s memory allocator and is used to store data structures associated with each client’s session, such as query plans and sorts. To tune the […]

PostgreSQL Redo Log: Can You Turn Off Generation?

No, it is not possible to turn off redo log generation in PostgreSQL, as it is a fundamental part of the transactional system that ensures the durability and consistency of your data. The redo logs […]

PostgreSQL COMMIT: What It Does Internally

In PostgreSQL, a COMMIT statement is used to finalize a transaction and make its changes permanent in the database. When a COMMIT statement is executed, the following things happen internally in PostgreSQL: After a transaction […]

MySQL Ransactions: What Happens to Uncommitted Transactions After a Crash

In MySQL, if the server crashes after an update and the transaction was not committed, the changes made by the transaction will be rolled back during the crash recovery process. This is because MySQL uses […]

SELECT * SQL Performance: Why SELECT * Is Bad

Using SELECT * can be bad for SQL performance for several reasons, including the following: Overall, it is best practice to only select the columns that are needed for a query, rather than using SELECT […]

PostgreSQL Latches: How They Are Implemented

PostgreSQL uses latches to provide synchronization between different threads accessing shared resources. Latches are lightweight and efficient mechanisms that provide mutual exclusion between threads. Here is a table describing all the PostgreSQL latches, their purpose, […]

Configuring PostgreSQL for optimal usage of available RAM

PostgreSQL has several configuration parameters that control its memory usage. Here is a detailed description of some of the most important memory-related parameters: It is important to monitor the memory usage of the database process […]