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Mongodb 指定要在group()查询中返回的字段_Mongodb_Field - Fatal编程技术网

Mongodb 指定要在group()查询中返回的字段

Mongodb 指定要在group()查询中返回的字段,mongodb,field,Mongodb,Field,如何指定在组查询中返回哪些字段?find具有字段参数;组不需要。编写一个javascript函数,删除您不需要的字段,并将其传递给组的finalize参数,这不会减慢查询速度吗?

如何指定在组查询中返回哪些字段?find具有字段参数;组不需要。编写一个javascript函数,删除您不需要的字段,并将其传递给组的finalize参数,这不会减慢查询速度吗?