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Practical Examples of Data Normalization in PostgreSQL
Normalization by Osmosis Part 2: Practical Examples of Data Normalization in PostgreSQL Having gone through a theoretical introduction in part 1, it is now time to discuss some more practical examples. I’ll first talk about the… type modeling … of columns. It is important to realize that during the time Codd formulated the base 3 […]
Data Normalization in PostgreSQL
Normalization by Osmosis Part 1: A Guide to Data Normalization in PostgreSQL By Michał Małecki Introduction Although I installed my first PostgreSQL database on RedHat Linux (not RHEL) 6.0 around 1999, I probably limited my interaction with this 6.5 release to starting the server with SysinitV scripts. PostgreSQL was at that time an underdog to […]
Manage encryption keys with PostgreSQL TDE
Manage encryption keys with PostgreSQL TDE PostgreSQL TDE is a version of PostgreSQL which offers on-disk encryption for PostgreSQL. Currently we at CYBERTEC maintain this piece of software for public use. What we have noticed recently is that people kept asking about how to integrate PostgreSQL TDE with existing key management solutions. To help you […]
zheap UNDO logs discarding in PostgreSQL
Some time ago, I posted some information about zheap, a storage engine for PostgreSQL. The idea behind zheap is to make UPDATE statements run faster in order to keep table bloat under control. Currently, PostgreSQL copies data on UPDATE and puts the copy of the row into the same data file. While this isn’t a […]
pg_rewrite: PostgreSQL Table Partitioning
PostgreSQL table partitioning is by far one of the most popular new PostgreSQL features. Many people look to partitioned tables as a way to improve performance and broaden scalability. However, partitioning comes with a little problem: How can you partition an existing table without locking up the database? The answer is: pg_rewrite can help you […]
Primary Keys vs. UNIQUE Constraints in PostgreSQL
Most of my readers will know about primary keys and all kinds of table constraints. However, only a few of you may have ever thought about the difference between a primary key and a UNIQUE constraint. Isn’t it all just the same? In both cases, PostgreSQL will create an index that avoids duplicate entries. So […]
Entity-attribute-value (EAV) design in PostgreSQL – don’t do it!
© Laurenz Albe 2021 Customers have often asked me what I think of “Entity-attribute-value” (EAV) design. So I thought it would be a good idea to lay down my opinion in writing. What is entity-attribute-value design? The idea is not to create a table for each entity in the application. Rather, you store each attribute […]
PostgreSQL on WSL2 for Windows: Install and setup
This post explains how to install PostgreSQL on WSL2 for Windows, apply the necessary changes to PostgreSQL settings, and access the database from the Windows host. Even though this knowledge can be found in different bits and pieces spread out all over the internet, I want to compile a short and straightforward how-to article. I […]
TCP keepalive for a better PostgreSQL experience
© Laurenz Albe 2021 If you’ve heard about TCP keepalive but aren’t sure what that is, read on. If you’ve ever been surprised by error messages like: server closed the connection unexpectedly SSL SYSCALL error: EOF detected unexpected EOF on client connection could not receive data from client: Connection reset by peer then this article […]
WITH HOLD cursors and transactions in PostgreSQL
© Laurenz Albe 2021 Both cursors and transactions are basic ingredients for developing a database application. This article describes how cursors and transactions interact and how WITH HOLD can work around their limitations. We will also see the dangers involved and how to properly use WITH HOLD cursors in a PL/pgSQL procedure. Cursors in PostgreSQL […]
SHOW TABLES in PostgreSQL: what’s wrong with it?
In this article, I will answer the questions: why isn’t there a SHOW TABLES command in PostgreSQL, when will SHOW TABLES in PostgreSQL be available, and how do I list tables with native PostgreSQL methods? Why isn’t there a SHOW TABLES command in PostgreSQL? People who come from MySQL are always asking the same question: […]
OpenStreetMap service by CYBERTEC
In response to repeated customer requests seeking spatial datasets based on the OpenStreetMap service, CYBERTEC decided to start an initiative to address this demand. CYBERTEC implemented a “download OpenStreetMap” service which periodically generates extracts of OpenStreetMap data in various forms, and outputs the data as an sql dump to streamline and simplify its usage. Extracts […]