Database Pages

A page is a fixed-sized block of data

• It can contain tuple, metadata, indexes, log records...

• Most systems do not mix page types

• Some system require a page to be self-contained

Each page is giving a unique identifier

• The DBMS uses an indirection layer to map page ids to physical locations

There are 3 different notions of "pages" in the DBMS:

• Hardware page (usually 4KB)

• OS Page (usually 4KB)

• Database Page (512B - 16KB)

By hardware page, we mean at what level device can guarantee a "failsafe write"