node.js - 使用 mongoose 切换数据库

Question

嗨，有没有办法用 Mongoose 切换数据库？我想我可以这样做:

mongoose.disconnect();
mongoose.connect('localhost',db);

但它不起作用我收到此错误:

Error: Trying to open unclosed connection.

不知道是不是因为是异步的

Answer 1

如前所述，您可以使用 useDb 函数来完成此操作:

示例代码:

async function myDbConnection() {

    const url = 'mongodb+srv://username:password@cluster0-pauvx.mongodb.net/test?retryWrites=true&w=majority';

    try {
        await mongoose.connect(url, { useNewUrlParser: true });
        console.log('Connected Successfully')
        // Here from above url you've already got connected to test DB,
           So let's make a switch as needed.
        mongoose.connection.useDb('myDB'); // Switching happens here..
        /**
         * Do some DB transaction with mongoose models as by now models has already been registered to created DB connection
         */
    } catch (error) {
        console.log('Error connecting to DB ::', error);
    }
}

或者，如果您想创建一个完整的新连接，那么您必须尝试 mongoose.createConnection()。仅供引用，如果使用 mongoDB 驱动程序，您将使用::

mongodb.MongoClient.connect(mongourl, function(err, primaryDB) {
  // open another database over the same connection
  const secondaryDB = primaryDB.db(SECONDARY_DATABASE_NAME);

  // now you can use both `database` and `database2`
  ...
});

引用: mongoose multiple different connections , mongoose useDb() , mongoDB driver switch connections