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Comment by carterschonwald | Hacker News Reader

Does this mean it’ll be easy to do graph transitive closure computations in sqlite now?

Do you mean iterating on an agency matrix dimension times to get the full path length between any two nodes?

I have had to run my recursive queries external to the database (MySQL, SQLite), this change looks to bring it into the database. Excellent news!

Transitive closure will tell you if a path between two nodes exists, not the length of the shortest path between two nodes.

You're technically correct, but afaik there isn't really a way to compute transitive closure without also computing shortest paths along the way, modulo constant factors?

You'll compute paths along the way but won't know that they're the shortest path. Odds are good though that you'll havr found something good enough for most purposes though.

If all you do is iterate over the adjacency matrix, sure, but wouldn't Floyd-Warshall be the same time complexity? All I'm saying is that you get both pieces of information for essentially the same price, modulo constant factors.

Even if it is, i imagine its not going to be that efficient if it isnt optimized for that use csse.

I solved a task involving transitive closures in last year's Advent of Code using SQLite:

https://github.com/nikeee/advent-of-code-2019/blob/master/06...

How could this be improved with the new feature of SQLite?

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