Question

I have table with 5 columns

------------------------------------------------------
|_id(mongo default)| link | name| street|zip | phone |
|------------------|------|-----|-------|----|-------|
|somethin          |23    |a    | b     |c   |1      |
|something *       |24    |a    | b     |c   |1      |
|something **      |27    |a2   | b     |c   |1      |
------------------------------------------------------

I want to find all the disctinct rows available ignoring the link column . Is it possible to do that way in mongo ? The above table would give me two rows .. 1st and 3rd

one way I figured out was to get disctint:name,street,zip,phone to get an array
and then query back where name=>name[0],street=> street[0],zip=>zip[0],phone=>phone[0]

Any better approach?

Answer 1

Since the distinct command can only accept one key field, you can use group() command or Map/Reduce to achieve what you want.

An example is given in this url – http://groups.google.com/group/mongodb-user/browse_thread/thread/5f571f39ee79b75f?pli=1