When you have this kind of demand, first consider whether it can be embedded. If it cannot be embedded, consider whether it is really not satisfied by a relational database.
In addition, when there is an index, the speed of obtaining data through reference is not bad, but it is more cumbersome to write the code yourself.
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http://docs.mongodb.org/manual/reference/database-references/
When you have this kind of demand, first consider whether it can be embedded. If it cannot be embedded, consider whether it is really not satisfied by a relational database.
In addition, when there is an index, the speed of obtaining data through reference is not bad, but it is more cumbersome to write the code yourself.