> For the complete documentation index, see [llms.txt](https://til.notdu.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://til.notdu.com/database/intro-to-database-systems/database-storage-ii/log-structured-file-organization.md).

# Log-structured file organization

Instead of storing tuple in pages, the DBMS only store log records

The system append log records to the file of how the database was modified:

![](https://2548495579-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTsnKOX7xLvOtvOXY9MlI%2Fuploads%2FDxZI7VMniyGEpdSM2gWA%2Fimage.png?alt=media\&token=dbaa16e1-4d7d-47ed-af46-d446289fcafd)

To read a record, the DBMS scan the log backwards and `recreates` the tuple to find what it needs

![](https://2548495579-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTsnKOX7xLvOtvOXY9MlI%2Fuploads%2FMjlacBQ3L2ei5vQIu0Q0%2Fimage.png?alt=media\&token=e2461240-5427-4597-a7be-9a5757bffbb8)