Database query optimizers are critical for performance, transforming SQL into efficient execution plans. This article explores the core techniques of query rewrite and logical optimization, including AST transformation, predicate pushdown, and join reordering. It explains how these methods reduce query complexity and improve execution speed. For engineers working on database internals or performance tuning, understanding these concepts is essential. The article provides clear examples and practical insights, making it a valuable resource for both learning and reference.
A deep dive into query rewrite and logical optimization techniques used in database query optimizers.