从SQL到MongoDB，这一篇就够了
复制{ _id: ObjectId("509a8fb2f3f4948bd2f983a0"),篇够 user_id: "abc123", age: 55, status: A} 1.2.3.4.5.6.
复制{ _id: ObjectId("509a8fb2f3f4948bd2f983a0"),篇够 user_id: "abc123", age: 55, status: A} 1.2.3.4.5.6.
复制{ _id: ObjectId("509a8fb2f3f4948bd2f983a0"),篇够 user_id: "abc123", age: 55, status: A} 1.2.3.4.5.6.