Hi, I'm trying to figure out what information retrieval model[1] the PostgreSQL Full-Text Search is based on. Based on my reading on the PostgreSQL documentation I would have guessed extended boolean model but I came across an web article by Compose[2] which claims that FTS is based on vector space model instead. The article does not offer anything to back this claim so I thought to ask here if anyone has more accurate details to share. I've tried to look this up from postgresql sources but so far I have not found anything. Timo 1: https://en.wikipedia.org/wiki/Information_retrieval#/media/File:Information-Retrieval-Models.png 2: https://www.compose.com/articles/indexing-for-full-text-search-in-postgresql/
