Understanding Table Lookups in InnoDB: Mechanisms and Reduction Techniques

Core Concept: What is a Table Lookup? In MySQL's InnoDB storage engine, tables are physically organized as B+ Trees built on the primary key (clustered index). Secondary indexes store both the indexed attribute values and the primary key of each matched row. When an execution plan selects a secondary index but the query requests columns absent ...

Posted on Sun, 12 Jul 2026 16:31:19 +0000 by silvercover