This article explains how Apache RocketMQ performs server‑side message filtering using Tag and SQL92 expressions, outlines the workflow for producers and consumers, compares the two methods, and provides Java code examples for implementing both simple tag filtering and advanced SQL‑based attribute filtering.
This article explains how to apply gray release techniques in RocketMQ by upgrading consumers, upgrading producers, and using consumer‑side filtering, tag filtering, and SQL92 filtering, providing concrete code examples, configuration steps, and trade‑off analysis for each approach.
This guide shows how to configure Spring Boot 2.3.9 with RocketMQ 4.8.0, add the necessary dependencies, and implement two message‑filtering methods—tag‑based and SQL‑92 expression‑based—complete with code samples, configuration snippets, and testing steps.
This article explains the MySQL COUNT function, compares COUNT(*), COUNT(1) and COUNT(column) usages, discusses common interview questions, and details the specific optimizations MyISAM and InnoDB apply to COUNT(*) queries, concluding with best‑practice recommendations.
