We are trying to develop a strategy for using elasticsearch for full-text searching on our mongodb instance. It would appear that every key that we want to use as a filter must be included in elastics index. Potentially we could want to use every key in mongo as a filter - i.e. full-text search on description, filter by date and telephone number. Does anyone have any real-world experiences of adding full-text to mongo that they can share?
Maybe we can just use elasticsearch as a db?
I do not see any reason to use ElasticSearch in conjunction with MongoDb, just use ElasticSearch as separate document storage for documents, that have to be searched. And yes, you can even as whole db. Of course it depends on your domain model and other factors.
If you don't need stemming, fuzzy search, complicated wildcard search, you can do search with mongoDb. When new document inserted, split it to words in lower case, and add to the array "words" for example. Later you can perform search request against this array with regex. Not you can' use I (ignore case) option in this regex, and you can search only LIKE% wildcard (or without wildcard), otherwise search would not use mongoDb index.
One more option - you can try to find river for mongoDb
Another option - is to use Lucene if you are using Java. Probably you will be able to extend Directory class, in such a way, that Lucene will store index in MongoDb instead of file system or RAM. I have not made any research in this area, but I think it is possible