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
Have you ever spent 20 minutes looking for a conversation you had with Cursor last week? The one where it helped you fix a tricky async bug—and now you're facing the same issue in a different project, but can't find that thread anywhere? This isn't a user error. It's a structural limitation in how Cursor handles session history. Cursor includes a built-in conversation history panel. You can browse
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
llms.txt is a small text file on a documentation site—usually lists what the product is and links to the important Markdown pages. For coding agents, treat it as the canonical URL to open first when upstream behavior is unclear. This post is mostly setup and workflow, not theory. Location Put this there Official doc server https://example.com/llms.txt (maintained by the library/vendor) Y
Billing code is the most dangerous place to have subtle bugs. It rarely crashes — it just silently does the wrong thing. Here are two we found and fixed in ClipCrafter, an AI video clip extraction tool. We track how many seconds of video each user processes per day to enforce plan limits. The original increment looked like this: const { data } = await db .from("users") .select("daily_usage_sec
This post was created with AI assistance and reviewed for accuracy before publishing. Cursor can use project rules and documentation to steer behavior. Exact file names and mechanisms evolve; check Cursor documentation for the current layout (for example rules in .cursor or legacy .cursorrules patterns). Short, enforceable bullets beat long essays: stack versions, test commands, “no new dependenci