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by MartinMond 4996 days ago
Is MongoDB actually able to combine 2 or more indices?
2 comments
jiryu 4996 days ago
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.
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MartinMond 4996 days ago
Yes of course, but it's kinda slow if you have to maintain one compound index for each possible query you're going to run, that's why I was asking.
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chmod775 4996 days ago
Nope, you can use the compound index 'a,b,c' to query over the following fields:

    a
    a.b
    a,b,c
The manual actually explains it like that.
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mattparlane 4996 days ago
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.

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