Development Team/Datastore Rewrite: Difference between revisions
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This improves storage efficiency in general, but in our case is more important because we wish to record in the journal several interactions that refer to the same file. For example, "Downloaded lesson3.pdf", "Read lesson3.pdf", "Sent lesson3.pdf to Juan" would all refer to the same file and we need to only store it once. | This improves storage efficiency in general, but in our case is more important because we wish to record in the journal several interactions that refer to the same file. For example, "Downloaded lesson3.pdf", "Read lesson3.pdf", "Sent lesson3.pdf to Juan" would all refer to the same file and we need to only store it once. | ||
== Layout on disk == | |||
The proposed implementation relies heavily on the data structures provided by the filesystem, thus the layout in which files are disposed on disk is a fundamental part of its design. | |||
Example of a datastore containing 5 entries, two of them referring to the same file (with checksum 464493d8d929436b6152e868867ed451): | |||
1a | |||
1ab88287-766a-4d98-a7c0-4233dc48647a | |||
1ab88287-766a-4d98-a7c0-4233dc48647a | |||
metadata | |||
2b | |||
2b90597c-0912-4e7f-8eeb-71a0f004490d | |||
2b90597c-0912-4e7f-8eeb-71a0f004490d -> checksums/464493d8d929436b6152e868867ed451 | |||
checksum ~> checksums/464493d8d929436b6152e868867ed451 | |||
extra_metadata | |||
preview | |||
metadata | |||
3c | |||
3cdf5f0e-7595-4166-b1f9-cbedfcfe1c4a | |||
3cdf5f0e-7595-4166-b1f9-cbedfcfe1c4a -> checksums/464493d8d929436b6152e868867ed451 | |||
checksum ~> checksums/464493d8d929436b6152e868867ed451 | |||
extra_metadata | |||
preview | |||
metadata | |||
4d | |||
4db11d29-2f07-4452-bd8e-22a6a483ac19 | |||
4db11d29-2f07-4452-bd8e-22a6a483ac19 | |||
metadata | |||
extra_metadata | |||
preview | |||
5e | |||
5e9f2027-b41e-4015-a848-6b3972193eb8 | |||
5e9f2027-b41e-4015-a848-6b3972193eb8 | |||
metadata | |||
extra_metadata | |||
preview | |||
checksums | |||
index | |||