Everybody who has ever written any kind of database application had to use time and date. However, in PostgreSQL there are some subtle issues most people might not be aware of. To make it easier for beginners, as well as advanced people, to understand this vital topic I have decided to compile some examples which […]

Hands-on time series forecasting with LSTM The idea of this post is to teach you how to build your first Recurrent Neural Network (RNN) for series prediction. In particular, we are going to use the Long Short Term Memory (LSTM) RNN, which has gained a lot of attention in the last years. LSTM solve the […]

Our PostgreSQL blog about “Speeding up count(*)” was widely read and discussed by our followers on the internet. We also saw some people commenting on the post and suggesting using different means to speed up count(*). I want to specifically focus on one of those comments and to warn our readers. max(id) – min(id) will […]

Last time I announced to checkout MobilityDB to improve our approach to extract overlapping passage times of healthy and infected individuals – here we go! MobilityDB itself is a PostgreSQL extension built on top of PostGIS, specializing on processing and analysing spatio-temporal data. To do so, the extension adds a bunch of types and functions […]

Usually in this blog I’m writing about various fun topics around PostgreSQL – like perhaps new cool features, some tricky configuration parameters, performance of particular features or on some “life hacks” to ease the life of DBA-s or developers. This post will be quite different though – inspired by an article I stumbled upon recently, […]

© Laurenz Albe 2020 Most people know that autovacuum is necessary to get rid of dead tuples. These dead tuples are a side effect of PostgreSQL’s MVCC implementation. So many people will be confused when they read that from PostgreSQL v13 on, commit b07642dbc adds support for autovacuuming insert-only tables (also known as “append-only tables”). […]

© Laurenz Albe 2020 In my daily work, I see many databases with a bad setting for max_connections. There is little advice out there for setting this parameter correctly, even though it is vital for the health of a database. So I decided to write up something. What is max_connections? According to the documentation, max_connections […]

In times of COVID-19, governments contemplate tough measures to identify and trace infected people. These measures include the utilization of mobile phone data to trace down infected individuals and subsequently contacts to curb the epidemic. This article shows how PostGIS’ functions can be used to identify “overlapping” sections of infected and healthy individuals by analysing tracks […]

2 weeks ago we announced a new, long awaited, Postgres extension to look into execution plans for “live” running queries: pg_show_plans. This was not possible before in PostgreSQL yet, so it’s really a very cool piece of functionality and we’d like to echo out the message again. So here in this blogpost we’ll reiterate some […]

Time Series Forecast In this post we will show how to approach a time series problem, using machine learning techniques. Predicting the behavior of a variable over time is a common problem that one encounters in many industries, from prices of assets on the stock market to the amount of transactions per minute on a […]

Recently I was talking in a more general way about some common auditing / change tracking approaches for PostgreSQL…but it also made me curious, how it roughly looks from the performance side? To quickly recap the previous blog post: the most common approaches for tracking important changes are mostly solved with writing some triggers. There […]

After 20 years in professional PostgreSQL support and consulting we are finally able to answer one of the most frequently asked questions: “How can I see all active query plans?” Ladies and gentlemen, let me introduce you to pg_show_plans, an extension which does exactly that. pg_show_plans is Open Source and can be used free of […]