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Dolt is Git for Data: a SQL database that you can fork, clone, branch, merge

(github.com)
752 points crazypython | 1 comments | 06 Mar 21 21:15 UTC | HN request time: 0.281s | source
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Nican ◴[07 Mar 21 00:39 UTC] No.26371964[source]▶
I love the idea of this project so much. Being able to more easily share comprehensible data is an interest of mine.

It is not the first time I have seen immutable B-trees being used as a method for being able to query a dataset on a different point in time.

Spanner (and its derivatives) uses a similar technique to ensure backup consistency. Solutions such as CockroachDB also allows you to query data in the past [1], and then uses a garbage collector to delete older unused data. The Time-to-live of history data is configurable.

[1] https://www.cockroachlabs.com/docs/stable/as-of-system-time....

replies(1): >>26372267 #
1. Nican ◴[07 Mar 21 01:30 UTC] No.26372267[source]▶
Albeit, now it makes me wonder how much of the functionality of dolt is possible to be replicated with CockroachDB. The internal data structures of both databases are mostly similar.

You can have infinite point-time-querying by setting the TTL of data to forever.

You have the ability to do distributed BACKUP/IMPORT of data (Which is mostly a file copy, and also includes historical data)

A transaction would be the equivalent of a commit, but I do not think there is a way to list out all transactions on CRDB, so that would have to be done separately.

And gain other benefits, such as distributed querying, and high availability.

I just find interesting that both databases (CockroachDB and Dolt) share the same principal of immutable B-Trees.