When you use window functions in SQL, you can't filter their results directly in a WHERE or HAVING clause — that's a well‑known limitation across many databases. GBase 8a, the China‑domestically developed MPP database from GBASE, solves this elegantly with the QUALIFY clause. Let's break down how it works, what it can do, and where you need to be careful. DROP TABLE IF EXISTS emp; CREATE TABLE emp
As data grows, you'll likely need to add nodes to your existing GBase 8a MPP cluster without downtime. This hands‑on guide walks through the full process of adding a composite GNode to a running GBASE cluster. Existing cluster: A healthy GBase 8a cluster New node: A server with a static IP address configured Network: All nodes must be able to communicate with each other Stop services on all existi
By default, identifiers in GBase 8s are case‑insensitive: uppercase letters are silently treated as lowercase. Setting the environment variable DELIMIDENT=Y changes how double‑quoted identifiers behave, enabling case‑sensitive table and column names. Here's a demonstration and a deep dive into the option, as used in a gbase database. With DELIMIDENT=y exported, execute the following statements: ex
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
Data is no longer treated as a byproduct of business operations and has become one of the most valuable organizational assets. Every interaction on a banking application, e-commerce platform, hospital system, logistics network or social media service generates data continuously. As organizations increasingly adopt digital workflows, cloud platforms, machine learning systems and real-time applicati
This article is an AI-assisted translation of a Japanese technical article. In April 2026, Amazon Bedrock AgentCore added a new capability called Optimization, which takes real agent traces and proposes prompt improvements based on them. https://aws.amazon.com/about-aws/whats-new/2026/05/bedrock-agentcore-optimization-preview/ In this article, I apply AgentCore Optimization to a Strands Agents-as-
DynamoDB Global Tables replicate data across regions in seconds, but replication is still asynchronous. That means a simple read from a replica region can occasionally return stale data, which is acceptable in most application as the user doesn’t require the latest available data all the time, but in some systems, stale reads can break important processes and stability of a platform. So the questi