有没有一种方法可以通过Node.js驱动程序检查Mongo中是否存在数据库? [英] Is there a way to check if a database exists in Mongo from the Node.js driver?

问题描述

我发现很难找到一种从Node.js驱动程序中查看数据库是否存在于MongoDB中的方法. 似乎在Node.js驱动程序中没有检查数据库是否存在的方法.

I'm finding it surprisingly difficult to see find a way to see if a database exists or not in MongoDB from the Node.js driver. There seems to be no method in the Node.js driver to check if a database exists.

例如，以下内容不会引发错误:

For example, the following doesn't throw an error:

var mongo = require('mongodb').MongoClient;

mongo.connect({ 'mongodb://localhost:27017/databaseThatDoesntExists }, function (err, db) {
   // There is no error
   if (err) console.log(err);
   // Let's get some stats on a database that doesn't exist
   db.statsAsync(function (err, result) {
      console.log(result);
   });
});

结果将是这样的对象:

{ db: 'databaseThatDoesntExist',
  collections: 0,
  objects: 0,
  avgObjSize: 0,
  dataSize: 0,
  storageSize: 0,
  numExtents: 0,
  indexes: 0,
  indexSize: 0,
  fileSize: 0,
  ok: 1 }

您能否通过Node.js驱动程序检查MongoDB中是否存在数据库? MongoDB中甚至存在数据库的概念吗?引用不存在的数据库只是引用没有集合的数据库吗?

Can you check to see if a database exists in MongoDB form the Node.js driver? Is there even a concept of a database existing in MongoDB? Is referencing a database that doesn't exist just referencing a database with no collections?

蒙哥，你为什么不能只抛出一个错误！我喜欢我的代码throws错误！

Mongo, why can't you just throw an error! I like when my code throws errors!

推荐答案

检查是否 db.admin().listDatabases 包含数据库名称.

Check if db.admin().listDatabases contains the database name.

如果服务器已启用授权，则需要适当的权限.

If the server has authorization enabled, you will need the appropriate permissions.

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