(PECL mongo >=1.3.0)
MongoClient::dropDB — 删除一个数据库 [已废弃]
This extension that defines this method is deprecated. Instead, the MongoDB extension should be used. There is no equivalent for this method in the new extension, but there is an alternative in the PHP library:
db
要函数的数据库。可以是一个 MongoDB对象，或者是数据库名。
返回数据库的回应。