http://docs.mongodb.org/manual/aggregation/
Design like this:
{ player: { id: 123, name: 'zhangsan', register_time: }, login_time: }
Then aggregate First filter by register_time, then group by login_time
I guess you still don’t know how to...
Also, I think, don’t do this, it requires a lot of calculations
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http://docs.mongodb.org/manual/aggregation/
Design like this:
Then aggregate
First filter by register_time, then group by login_time
I guess you still don’t know how to...
Also, I think, don’t do this, it requires a lot of calculations