Beyond a basic query with a join or two, many queries require extracting subsets of data for comparison, conditionals, or aggregation. Postgres’ use of the SQL language is standards compliant and SQL has a world of tools for subqueries. This post will look at many of the different subquery tools. We’ll talk about the advantages and use cases of each, and provide further reading and tutorials to dig in more.

I’ll take a broad definition of “subquery”. Why am I calling all of these subqueries? These are all queries that work on subsets of data. Having read the article title, you might have come here to say that a subquery is a specific thing vs

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We've also loaded a tutorial for Day 19's challenge

Postgres wasn't always the cool kid. It didn't emerge from millions of dollars of VC funding, it didn't have a team of DevRel evangelists championing it, it simply started and evolved. Postgres just passed the 25 year milestone as an open source project. With the upcoming release of Postgres 16 in coming months, we thought we'd pause for a minute and take a look back at Postgres and how it got to where it is today.

If for some reason you've been living under a rock and are unfamiliar with Postgres, give a read on our write-up of Why Postgres

Last week, Randall Munroe dropped his latest XKCD "Bad Map Projection", number six, "ABS(Longitude)", which looks like this:

Truly this is a bad map projection, on a par with the previous five:

• Liquid Resize

In my last blog post, I showed four ways to access a remotely hosted CSV file from inside PostgreSQL:

• Using the COPY command with the PROGRAM option,
• Using the http extension

Today we're excited to announce several big improvements to Crunchy Bridge to make it easier to work with your database without having to become a DBA. Today we're releasing:

• Database insights: Real-time indicators to ensure a healthy database
• Metrics: Monitor your system over time
• Production check: Ensure you're ready for launch day

We are happy to unveil the newest release of Crunchy Postgres for Kubernetes version 5.4. This update brings an array of features set to improve your experience including:

• Support for ARM
• Native vector search via pgvector
• Comprehensive support for huge pages
• Native support for Postgres tablespaces
• Documentation enhancements

This article will contain spoilers both on how I solved 2022 Day 18's challenge "Boiling Boulders" using SQL, as well as general ideas on how to approach the problem. I recommend trying to solve it yourself first, using your favorite language.

(heatmap slicing a 3-D piece of lava - all in SQL!)

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We have a lot of Postgres foreign data wrapper (FDW) users here at Crunchy. The postgres_fdw lets you connect to remote servers and in some cases can be an alternative for traditional ETL/ELT processes. As I see use of the Postgres foreign data wrapper expanding, I wanted to make some recommendations on how to approach performance. When you query from a single Postgres cluster, the database cleverly uses internal statistics to auto-tune performance

Solving Advent of Code 2022 using Postgres - Day 17

(Yes, this image was generated completely by SQL statements!)

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