Re: FTS and tri-grams

> On Jan 5, 2021, at 13:26, Mark Phillips <mark(dot)phillips(at)mophilly(dot)com> wrote:
> 1. Is FTS required for tri-gram to work?
> 2. Are these independent of each other?
> 3. Is tri-gram alone sufficient for a “full text search” feature?

The answers are, kind of in order:

2. Yes.
1. No.
3. It depends on what you mean by "full text search."

Trigrams are mostly for fuzzy matching on a single or small number of words. There are things that the tsvector machinery can do that trigrams can't, such as proximity searches between words, prefix and stemmed searches, and things of that type. If you just want fuzzy searching on a small number of words, trigrams are probably fine; for more sophisticated kinds of searching, you want tsvector.

They're completely different sets of functionality in PostgreSQL.

--
-- Christophe Pettus
xof(at)thebuild(dot)com