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171 points voat | 2 comments | | HN request time: 0.4s | source
1. Agraillo ◴[] No.42159668[source]
I think it is a good direction imho. Once being familiar with SQL I learned Prolog a little and similarities struck me. I wasn't the first one sure, and there are others who summarized it better than me [1] (2010-2012):

Each can do the other, to a limited extent, but it becomes increasingly difficult with even small increases in complexity. For instance, you can do inferencing in SQL, but it is almost entirely manual in nature and not at all like the automatic forward-inferencing of Prolog. And yes, you can store data(facts) in Prolog, but it is not at all designed for the "storage, retrieval, projection and reduction of Trillions of rows with thousands of simultaneous users" that SQL is.

I even wanted to implement something like Logica at the moment, primarily trying to build a bridge through a virtual table in SQLite that would allow storing rules as mostly Prolog statements and having adapters to SQL storage when inference needs facts.

[1]: https://stackoverflow.com/a/2119003

replies(1): >>42163667 #
2. cess11 ◴[] No.42163667[source]
Perhaps you already know this, but as a data store Prolog code is actually surprisingly convenient sometimes, similar to how you might create a throwaway SQLite3 or DuckDB for a one-off analysis or recurring batched jobs.

It's trivial to convert stuff like web server access logs into Prolog facts by either hacking the logging module or running the log files through a bit of sed, and then you can formalise some patterns as rules and do rather nifty querying. A hundred megabytes of RAM can hold a lot of log data as Prolog facts.

E.g. '2024-11-16 12:45:27 127.0.0.1 "GET /something" "Whatever User-Agent" "user_id_123"' could be trivially transformed into 'logrow("2024-11-16", "12:45:27", "127.0.0.1", "GET", "/something", "Whatever User-Agent", "user_id_123").', especially if you're acquainted with DCG:s. Then you could, for example, write a rule that defines a relation between rows where a user-agent and IP does GET /log_out and shortly after has activity with another user ID, and query out people that could be suspected to use several accounts.