It really depends on the setup that the dev/ops at customer are more comfortable with. Elastic or PostgreSQL can be both fine.
Personally for small cases (e.g. under 50k documents and 20GB of text) I like to use SQLite FTS, while linking text fragments to the additional metadata (native or extracted). This way I can really narrow down the search scope to a few case related documents in each conversation path.
But ultimately the flavor of DB and FTS is just an implementation detail. Most of them will do just fine.
Personally for small cases (e.g. under 50k documents and 20GB of text) I like to use SQLite FTS, while linking text fragments to the additional metadata (native or extracted). This way I can really narrow down the search scope to a few case related documents in each conversation path.
But ultimately the flavor of DB and FTS is just an implementation detail. Most of them will do just fine.
Edit: fixed grammar.