Optimizing MongoDB Compound Indexes

[Loic]

About 2 years ago (time is flying) I explained how I did the same to support range queries over "n" attributes, the method ended up being in the book "MongoDB, the Definitive Guide" by Chodorow and Dirolf (O'Reilly):

http://chemeo.com/doc/technology

(Search for "Indexing For High Speed Search" to skip non MongoDB related information).

[dkhenry]

What should be added to this is the ability to tell Mongo to return an error if your query requires a table scan. That one configuration item can be the difference between a request returning an error and a whole site going down for an extended period.

[pbrumm]

There is a config setting for that

  notablescan = true

http://docs.mongodb.org/manual/reference/configuration-optio...

[lucian1900]

You can ask it to explain what it did, just like you'd ask for the last error. Then in your app enforce whatever rules related to indexes you wish.

[MartinMond]

Is MongoDB actually able to combine 2 or more indices?

[jiryu]

No - it can only use one for a given query. But a compound index like the ones I describe in the post can index many fields.

[mattparlane]

You may be interested in this:

https://jira.mongodb.org/browse/SERVER-3071

It's index intersection, and it's scheduled for 2.3.1 which is the next next dev release. I'm hoping it makes it in for 2.4.