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Comment by ipnon | Hacker News Reader

While web programming in Prolog has been insightful, I think there are more expedient areas of application for the language.

Prolog is especially underutilized in databases.

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This is a database written in Prolog: https://github.com/terminusdb/terminus-server - albeit with a RUST storage engine - prolog's lack of types means there are better storage solutions, but for constraint logic, it's unbeatable.

A statically typed logic language would be ideal for both

https://mercurylang.org/

Mercury is cool. I translated a simple Prolog program to it once, and it was a head trip. Hard to get my mind around, but also helped me see the connection between functions and relations.

We evaluated the use of Mercury before settling on prolog for terminusDB. Mercury is a great language, but the community and library support is just a bit too small.

Prolog is already a database, why bring in the mess of an external DB. I have used Prolog and ODBC to access a postgres DB. I found it better to just export the data and turn it into a Prolog DB then process my rules than have it run all those logic across the wire.

What about performance?

For Clojure, there is Datomic[0] (a DB with S-expression Datalog) and DataScript[1] (in memory Datalog for browser) which has a fair amount of usage. Also, there's a bitemporal database use Datalog name Crux[2] seems to be quite promising.

[0] https://www.datomic.com/ [1] https://github.com/tonsky/datascript [2] https://opencrux.com/

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