MongoDB - too much data for sort() with no index error

Question

I am using MongoDB 1.6.3, to store a big collection (300k+ records). I added a composite index.

db[\'collection_name         


        

Answer 1

Even with an index, I think you can still get that error if your result set exceeds 4MB.

You can see the size by going into the mongodb console and doing this:

show dbs
# pick yours (e.g., production)
use db-production
db.articles.stats()

I ended up with results like this:

{
"ns" : "mdalert-production.encounters",
"count" : 89077,
"size" : 62974416,
"avgObjSize" : 706.9660630690302,
"storageSize" : 85170176,
"numExtents" : 8,
"nindexes" : 6,
"lastExtentSize" : 25819648,
"paddingFactor" : 1,
"flags" : 1,
"totalIndexSize" : 18808832,
"indexSizes" : {
    "_id_" : 3719168,
    "patient_num_1" : 3440640,
    "msg_timestamp_1" : 2981888,
    "practice_id_1" : 2342912,
    "patient_id_1" : 3342336,
    "msg_timestamp_-1" : 2981888
},
"ok" : 1
}