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PostgreSQL Query Rewriting Techniques The previous articles in this series covered performance problems you fix by adding indexes, restructuring joins, or tuning memory. This one is about the queries where the plan is "fine" — every node is doing something reasonable — but the query itself is asking the wrong question, producing unnecessarily large intermediate results or forcing the planner dow
This section is the map for the rest of the book. The five stages introduced in the 1.1 chapter overview (parse, analyze/rewrite, plan, portal, execute) are traced here through the actual code: which functions implement each stage, and in what order they get called. The mechanics of each of the five stages are unpacked in later chapters. Here, only the skeleton matters: how a backend starts up, ho
PostgreSQL Internals · Chapter 1 Query Processing Suppose a client sends SELECT * FROM users WHERE id = 1. The path that single line travels before coming back as a result row is longer than you might expect. Inside the PostgreSQL backend, that SQL goes through a five-stage pipeline. Backend entry and dispatch. The backend receives the message from the client and decides which processing path it s
In today’s world, learning skills like coding is more important than ever. But many students struggle to find the right guidance, support, and environment to grow. That’s where Master Coding Org (MCO) comes in. Master Coding Org (MCO) was created with a simple mission: Make learning coding accessible, collaborative, and practical for everyone. Instead of learning alone, MCO focuses on building a c
r/startpages Is the Most Underrated Firefox Community You're Not Using If you care about browser customization, there's a subreddit you probably haven't found yet: r/startpages. With 35,000+ members, it's a community of people who genuinely care about what appears when they open a new browser tab. They share custom HTML/CSS homepages, new tab extensions, and browser startpage setups. The r/start
SQL is widely known for data querying and manipulation but systems do grow; data becomes larger; processes become repetitive and operations become sensitive. SQL has some features which enables it to be considered a fully fledged programming language. Some of the features which I discuss in this article are procedures, functions and transactions. Each of these concepts serve distinct purposes. Sto
Introduction Placing RDS in a private subnet protects it from unauthorized external access — but it also means you can no longer connect directly from your developer machine. This article walks you through a step-by-step guide to securely connect to a private-subnet RDS (PostgreSQL) instance using AWS Client VPN. Developer PC │ │ UDP 443 (TLS / Mutual Certificate Authentication) ▼ Client