Question

I’m looking to search for a particular JSON document in a bucket and I don’t know its document ID, all I know is the value of one of the sub-keys. I’ve looked through the API documentation but still confused when it comes to my particular use case:

In mongo I can do a dynamic query like:

bucket.get({ "name" : "some-arbritrary-name-here" })

With couchbase I’m under the impression that you need to create an index (for example on the name property) and use startKey / endKey but this feels wrong – could you still end up with multiple documents being returned? Would be nice to be able to pass a parameter to the view that an exact match could be performed on. Also how would we handle multi-dimensional searches? i.e. name and category.

I’d like to do as much of the filtering as possible on the couchbase instance and ideally narrow it down to one record rather than having to filter when it comes back to the App Tier. Something like passing a dynamic value to the mapping function and only emitting documents that match.

I know you can use LINQ with couchbase to filter but if I’ve read the docs correctly this filtering is still done client-side but at least if we could narrow down the returned dataset to a sensible subset, client-side filtering wouldn’t be such a big deal.

Cheers

Answer 1

So you are correct on one point, you need to create a view (an index indeed) to be able to query on on the content of the JSON document.

So in you case you have to create a view with this kind of code:

function (doc, meta) {
 if (doc.type == "youtype") { // just a good practice to type the doc
   emit(doc.name);
 }
}

So this will create a index – distributed on all the nodes of your cluster – that you can now use in your application. You can point to a specific value using the “key” parameter