SitePoint Sponsor

User Tag List

Results 1 to 6 of 6
  1. #1
    Always A Novice bronze trophy
    K. Wolfe's Avatar
    Join Date
    Nov 2003
    Location
    Columbus, OH
    Posts
    2,079
    Mentioned
    53 Post(s)
    Tagged
    0 Thread(s)

    MongoDB Aggregate()

    Looks like a project of mine will be utilizing MongoDB, and this is just a whole new ball game to me... I cant for the life of me get my head around the aggregate function, all the examples I find seem to be off my learning style.

    Assuming I have SOME_ID and SOME_COUNT in a "document" or a row, how would I write the equivelent:

    Code:
    select
    some_id, sum(some_count)
    from
    myCollection
    group by
    some_id

  2. #2
    Always A Novice bronze trophy
    K. Wolfe's Avatar
    Join Date
    Nov 2003
    Location
    Columbus, OH
    Posts
    2,079
    Mentioned
    53 Post(s)
    Tagged
    0 Thread(s)
    After taking lunch I tried again with success:

    Code:
    db.myCollection.aggregate([{$group: {_id: "$some_id", count: {$sum: 1}}}]);
    I don't fully understand it but hey.. Now I need to figure out how to add in $where...

  3. #3
    Keeper of the SFL StarLion's Avatar
    Join Date
    Feb 2006
    Location
    Atlanta, GA, USA
    Posts
    3,747
    Mentioned
    64 Post(s)
    Tagged
    0 Thread(s)
    I.. think (and i could be wrong - it's been all of 30 seconds reading the aggregation documentation) that it would be something along the lines of...

    Code:
    db.myCollection.aggregate({$match: {field : "value"}},{$group: {_id: "$some_id", count: {$sum: 1}}});
    Never grow up. The instant you do, you lose all ability to imagine great things, for fear of reality crashing in.

  4. #4
    Always A Novice bronze trophy
    K. Wolfe's Avatar
    Join Date
    Nov 2003
    Location
    Columbus, OH
    Posts
    2,079
    Mentioned
    53 Post(s)
    Tagged
    0 Thread(s)
    Yeah I got it figured out, I'll put some examples here later. My biggest problem was the syntax as I had never seen JSON style before and if you don't know it, it can be very hard to stop problems.

  5. #5
    Hosting Team Leader silver trophybronze trophy
    cpradio's Avatar
    Join Date
    Jun 2002
    Location
    Ohio
    Posts
    4,813
    Mentioned
    141 Post(s)
    Tagged
    0 Thread(s)
    Not sure if this would be of any help, but I used to use http://jsonviewer.codeplex.com/ when I needed to verify the json I received or created was valid. Maybe there is something better for MongoDB out there, but if not, this will provide some help.
    Be sure to congratulate xMog on earning April's Member of the Month
    Go ahead and blame me, I still won't lose any sleep over it
    My Blog | My Technical Notes

  6. #6
    Always A Novice bronze trophy
    K. Wolfe's Avatar
    Join Date
    Nov 2003
    Location
    Columbus, OH
    Posts
    2,079
    Mentioned
    53 Post(s)
    Tagged
    0 Thread(s)
    Ah cool thank you! I think I'm getting the hang of it, and it looks like JSON / Mongo might be my life for awhile


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •