Possible to sort by multiple keys?

[D. Smith]

Is it possible to sort results by 2 or more keys?

In analogy to mysql, I need something like this:

SELECT * FROM FORUM_POSTS
ORDER BY
is_sticky ACS,
last_modified DESC

So basically I need to select items from forum_posts collection and
have posts marked with 'is_sticky' = true to appear first,
followed by posts ordered by last_modified time

Is it possible and how does mongo handle this? I mean - will it use 2
keys: is_sticky and last_modified or should I create a composite key?
I would rather not do a composite key unless it is really the best
option.

Thanks.

[Scott Hernandez]

Yes, you can sort by multiple fields; it almost never a good idea to
concatenate multiple fields together to make a new one.

find().sort({field1:1, field2:0}) for example.

http://www.mongodb.org/display/DOCS/Querying#Querying-Sorting

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[Scott Hernandez]

Sorry, 1 = ascending, -1 = descending.

The 0 below is a typo.

[D. Smith]

[Scott Hernandez]

Yes, see my previous response.

[Luiz Felipe Mendes]

Hello,

I'm very sorry to be resuscitating this old thread, but I would like to know, what is the best index to use in queries with multiples sort fields. 

Like:

db.Collection.find({ "$and" : [ { "m" : BinData(0,"wzlbR39bEokaufRAta5/hw==")}], "lala" : true , "date" : { "$gte" :  ISODate("2013-01-22T03:00:00.000Z")} ,  "date" : { "$lte" : ISODate( "2013-01-29T20:48:44.000Z")} , "o.lol" : { "$in" : [ 0 , 2]}}).limit(10).sort({"date":1,"id":1})

ps: In this case, the results will be ordered first by "date" and then by "id", right?

Thanks

[Nirmalkumar Seshachalam]

Dear Sir,

find().sort({field1:1, field2:1})

Looks does not work. For example I tried to apply on following data

https://education.10gen.com/static/m101j-may-2013/handouts/grades.839101a18c6f.json

The structure is like this: { "_id" : { "$oid" : "513257f68d6e7cb63d7b1c1f" }, "student_id" : 0, "type" : "homework", "score" : 78.45394447385343 }

In this I tries to sort first on student_id and then on score. This is essentially to list(table) each students record in the order of their score. So I tried the query bellow

db.grades.find().sort({student_id:1},{score:1})

It does not help me to achieve the desired result. Could you pls help?

Thanks,

Nirmalkumar Seshachalam

[Sam Millman]

db.grades.find().sort({student_id:1,score:1})

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