Trinity

and boolean operators is one thing, and Lucene/Solr, and Trinity (https://github.com/phaistos-networks/Trinity) among other technologies can be used to take care of those challenges. But that’s the easy part (assuming you can do this fast enough, because you almost always can’t afford long-running queries): - User Interfaces: Not just how results are presented, but also how users can construct or input queries. What options can be come available for filtering matches? - Ranking: Precision is key, and rather simple formulas (tf/idf, BM25, etc) generally don’t work well for many/most domains. Furthermore, ranking is almost always not just about relevancy. It factors in static context scores (e.g document “popularity”), personalisation biases(how likely is it for user to mean Soccer or American Football for [football]),and other signals, fused together somehow to determine the final ranking of matched documents. - Scale: Getting everything right is one thing, getting everything right at massive scale is whole different game. What may work on small scale(algorithms, technologies, services) may not work at all when you scale out. - Everything else not directly related to search but either important or fundamental to a good experience/business: from matching queries to ads, to analytics, to autosuggestions, to training ML models to power all that, etc. Web search is not a zero sum game. Bing makes over 3nb / year and while it may not have a chance to catch up with Google anytime soon, that’s a great business right there. Ditto for DDG. There are also companies that offer a different or better experience and access to datasets google doesn’t yet. So, all told, search may be solved only in terms of the basic IR technology that makes it all work, and arguably a lot better than it used to be in terms of user interfaces, ranking, etc, but it will take a lot longer until those other aspects of web search may be considered ‘solved’.

her such operations implementations are pretty much common across IR systems as well, with little room for improvement. To get great results, you need really great relevance models(1), a great query rewrite system(2), and, because query rewrites usually expand a query to include multiple disjunctions (OR terms and phrases), your search engine needs to be particularly efficient at handling those(3). You also need to care for spelling suggestions and personalisation/content biases and factors, but those are secondary concerns.