Page Merge — 2 Technical Articles

Dec 9, 2025 · Databases

Why UUID Primary Keys Trigger InnoDB Page Splits and How to Prevent Them

This article explains the internal mechanics of MySQL 8.0 InnoDB pages, how random primary keys such as UUID cause costly page splits and merges, and provides Java‑level best practices and MySQL commands to optimize primary‑key design for better performance and space utilization.

InnoDBMySQLPage Merge

0 likes · 14 min read

Why UUID Primary Keys Trigger InnoDB Page Splits and How to Prevent Them

dbaplus Community

Feb 10, 2022 · Databases

Why MySQL Delete Doesn’t Free Space and How InnoDB Reclaims It

This article explains why MySQL’s DELETE only sets a delete‑mark, how InnoDB’s MVCC and purge thread reuse freed pages, the impact of B+‑tree storage on I/O, page merge and split mechanisms, and the proper way to rebuild tables to recover space.

B+TreeDatabase StorageDelete Mark

0 likes · 14 min read

Why MySQL Delete Doesn’t Free Space and How InnoDB Reclaims It