Question

我有2个MongoDB集合，集合1看起来像这样：

Coll1:

{
   _id: 123456789,
   isbn: "123456"
   title: "MongoDB: The Definitive Guide",
   author: [ "Kristina Chodorow", "Mike Dirolf" ],
   published_date: ISODate("2010-09-24"),
   pages: 216,
   language: "English",
   publisher_id: "oreilly"
}

{
   _id: 234567890,
   isbn: "456789"
   title: "50 Tips and Tricks for MongoDB Developer",
   author: "Kristina Chodorow",
   published_date: ISODate("2011-05-06"),
   pages: 68,
   language: "English",
   publisher_id: "oreilly"
}

{
   _id: 234567891,
   isbn: "888222"
   title: "PostgreSQL: Up and Running",
   author: "Regina O. Obe, Leo S. Hsu",
   published_date: ISODate("2011-05-06"),
   pages: 68,
   language: "English",
   publisher_id: "oreilly"
}

和collection2看起来像这样：

Coll2:

{
  isbn: "123456",
  category: "NoSQL",
  gender: "male"
}

}
  isbn: "456789",
  category: "NoSQL",
  gender: "male"
}

}
  isbn: "888222",
  category: "SQL",
  gender: "male"
}

我需要迭代集合2中的所有文档，匹配集合1中的ISBN号，然后将类别字段添加到集合1中的相应文档。

e.g。

{
   _id: 234567891,
   isbn: "888222"
   title: "PostgreSQL: Up and Running",
   author: "Regina O. Obe, Leo S. Hsu",
   published_date: ISODate("2011-05-06"),
   pages: 68,
   language: "English",
   publisher_id: "oreilly",
   category: "NoSQL"
}

使用Mongo shell或Python可以实现此目的的最佳方法是什么？

Answer 1

在Mongo Shell中，您可以使用以下代码：

db.Coll2.find().forEach(function(c2){ 
 db.Coll1.update({isbn:c2.isbn},{$set: {category:c2.category}},{multi:true})
});

从集合更新集合

1 个答案: