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MVCC – the part of PostgreSQL we hate the most (2023)

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366 points virtualwhys | 1 comments | 20 Oct 24 15:30 UTC | HN request time: 0.001s | source
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nightfly ◴[20 Oct 24 18:26 UTC] No.41897421[source]▶
> MySQL and Oracle store a compact delta between the new and current versions (think of it like a git diff).

Doesn't git famously _not_ store diffs and instead follows the same storage pattern postgres uses here and stores the full new and old objects?

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jmholla ◴[20 Oct 24 18:31 UTC] No.41897457[source]▶
That is correct. Each version of a file is a separate blob. There is some compression done by packing to make cloning faster, but the raw for git works with is these blobs.
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thaumasiotes[dead post] ◴[20 Oct 24 18:42 UTC] No.41897535[source]▶
[flagged]
1. simonw ◴[20 Oct 24 19:15 UTC] No.41897771[source]▶
Saying "that's incorrect" is a lot more productive than saying "that's a lie".

Calling something a lie implies that the incorrect information was deliberate.