As you said some-word -> [doc385, doc211, doc39977, …] (sorted by rank, descending), I think the search engine may not do this, the doc list should be sorted by doc ID, each doc has a rank according to the word. When a query comes, it contains several keywords. For each word, you can find a … Read more
If you’re going to work with Lucene, I’d buy a good book that covers it from A to Z. Lucene has a very steep learning curve (in my opinion). It’s not only knowing how to search your that’s important – it’s also about indexing it. Doing a basic search is easy, but creating an index … Read more
Full text search is good for finding words, not substrings. For substring searches you’d better use like ‘%don%’ with pg_trgm extension available from PostgreSQL 9.1 and using gin (column_name gin_trgm_ops) or using gist (column_name gist_trgm_ops) indexes. But your index would be very big (even several times bigger than your table) and write performance not very … Read more
A bit old question, but the info might be helpful anyway. The index/mapping structure mainly depends on your usecase. Do you need to use all the languages simultaneously or only one language is used at time? Option 1: multilanguage website for example – the users only see and search in the current language they have … Read more
As at MongoDB 3.4, the text search feature is designed to support case-insensitive searches on text content with language-specific rules for stopwords and stemming. Stemming rules for supported languages are based on standard algorithms which generally handle common verbs and nouns but are unaware of proper nouns. There is no explicit support for partial or … Read more