Why $in is much faster than $all?

Question

db.tablebusiness.find({ \"LongitudeLatitude\" : { \"$nearSphere\" : [106.772835, -6.186753], \"$maxDistance\" : 0.053980478460939611 }, \"Prominent\" : { \"$gte\" : 15 }         


        

Answer 1

You are comparing apples with oranges. Both queries return different results. $all means that the field value should match all the inputs whereas $in means that the field value should match any one of the values. $all is and, $in is or.

Combined with the $limit - the $all query will need to look at more documents to find the match as compared to in.

Answer 2

I asked a similar question in Why using $all in mongodb is much slower?

This time I use only one word. Hence, there should be no difference between $in and $all. They both are equivalent.

Still $all is much slower.

Turns out, per answer on that, there is a bug in mongodb itself.

https://jira.mongodb.org/browse/SERVER-1748

I guess I simply won't use $all at all until the problem is fixed.

To all other answers, have you tried this your self?