Searching by key in Apache CouchDB

Question

Is it possible to search by key value in Apache CouchDB? Given the sample data below (spaced for readability):

{
    "_id":"a754a63dcc7f319b02f7ce6de522ca26",
    "_rev":"1-5bd88e53fe0869b8ce274b49a2c1ddf5",
    "name":"john smith",
    "email":"[email protected]",
    "username":"jsmith"
}

Could I query the database for the user jsmith or for the user having the email [email protected]? How would I go about this?

Answer 1

Yes, that is certainly possible. You will create a couple of views, which are sorted lists ("index") of your data, one per key.

Tobias's link is useful. However the standard CouchDB documentation will cover this also:

• Finding your data with views in the book (I prefer this resource)
• Introduction to CouchDB views in the wiki

For example, in your design document, you might want a users_by_email view, with keys based on the email field; then a users_by_name view keyed on the username field, etc. Experiment with the temporary views in Futon until you get your function working just right, and then store it in your design document permanently.

Good luck!

P.S. There is a way to combine all of these requirements into one view. Briefly, you could key on ["email", "[email protected]"] or ["name": "john smith"] however remember, CouchDB is relaxed: The simpler method above will work fine. When you become comfortable with views, you can explore this "collated" style.

Answer 2

http://sitr.us/2009/06/30/database-queries-the-couchdb-way.html

Answer 3

You cannot search by a keyvalue. You can only search by keys.

If you want to search for emails, emit [email, whatever data] in some view and add ?key='search email' to view url.

Searching only by keys gives huge performance benefits and hence this feature [searching by key value] will never ever come to couchDB.