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【MongoDB】The connection between two tables,mongodbtable

【MongoDB】The connection between two tables,mongodbtables


In mongoDB, there are two general way to connect with two tables. Manual Connection and use DBRef

1. Basically manual connection 

Firstly init the data which was saved in the different collections. 

The result:

2 usage of  DBRef

grammar: 


the example: 


Attention: the above example has some question;



The( )between the two playing periods of a football game is only a few minutes

5. proposal 提建议
4. captured 抓住
3. amused 觉得有意思
2 when 当她去那个地方时,她玩的很高兴
1. interval 间隔
 

He doesn`t even know where the difference between the two lies,which surprises us all 句中,为何

句意:他甚至不知道这两个东西不同的地方在哪里,这点使我们都很吃惊。
注意到这里的lie不是“谎言”的意思,而是“位于”的意思。
不同的地方位于哪里,肯定是这么个说法的,所以用的是where
而如果改成以下的,就可以用what了:
what the difference between the two is
这个时候的意思就是:这两个东西的不同点是什么

希望帮助到你~!
 

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