File Organization
Cost Model
Page
A page is typically 4k or 8k bytes.
Records are packed into pages.
- Dense packing: E.g. 4K page, 100 bytes records
→ 40 records/page.
- Pages aren't usually completely full: Due to
updates, pages tend not to be completely full. 50-70% is not
uncommon. (See B-tree discussion later.)
- Compression: Compression can be used to pack
more records per page. Amount of compression highly dependent on
data.
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