NOT NULL

macrozheng

Apr 14, 2021 · Databases

Why You Should Avoid NULL Columns in MySQL: Performance, Storage, and Index Impacts

This article explains why setting MySQL columns to NOT NULL improves query optimization, reduces index complexity, saves storage space, and prevents unexpected behavior in calculations, while also detailing default values, handling of NULL in aggregates, and the internal row format differences between NULLable and NOT NULL columns.