Search full document in mongodb for a match

Question

Is there a way to match a value with every array and sub document inside the document in mongodb collection and return the document

{
  "_id" : "2000001956",
  "trimline1" : "abc",
  "trimline2" : "xyz",
  "subtitle"  : "www",
  "image" : {
    "large" : 0,
    "small" : 0,
    "tiled" : 0,
    "cropped" : false
  },     
  "Kytrr" : {
      "count" : 0,
      "assigned" : 0
  }

}

for eg if in the above document I am searching for xyz or "ab" or "xy" or "z" or "0" this document should be returned.

I actually have to achieve this at the back end using C# driver but a mongo query would also help greatly.

Please advice.

Thanks

Answer 1

You could probably do this using '$where'

db.mycollection({$where:"JSON.stringify(this).indexOf('xyz')!=-1"})

I'm converting the whole record to a big string and then searching to see if your element is in the resulting string. Probably won't work if your xyz is in the fieldnames!

You can make it iterate through the fields to make a big string and then search it though.

This isn't the most elegant way and will involve a full tablescan. It will be faster if you look through the individual fields!

Answer 2

While Malcolm's answer above would work, when your collection gets large or you have high traffic, you'll see this fall over pretty quickly. This is because of 2 things. First, dropping down to javascript is a big deal and second, this will always be a full table scan because $where can't use an index.

MongoDB 2.6 introduced text indexing which is on by default (it was in beta in 2.4). With it, you can have a full text index on all the fields in the document. The documentation gives the following example where a text index is created for every field and names the index "TextIndex".

db.collection.ensureIndex(
    { "$**": "text" },
    { name: "TextIndex" }
)