What’s the relationship between files and pages in dbms
content
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a database (basically a collection of different tables) is stored on disks as files
- files could be heap file, or sorted files
- more common is heap file + indexes
- e.g., sqlite stores the whole database in a single file
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a file is like a binder, pages are different sheets in the binder, records (or tuples) are lines written in each of these pages
- a file is a OS concept, underneath it’s blocks of binary data
- a page corresponds to a block of data (the smallest unit of data access)
dbms-files-and-pages.excalidraw
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Excalidraw Data
Text Elements
file
page
header
page stores records
dbms
finds db file
based on RecordId finds PageId and SlotId
finds record
user query record
header
101011101..
111011101..
101000101..
101011101..
files
logical concepts
111011101..
page
physical existence
files are just collections of blocks of data
each block of data is called a page
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