初次注意到mongo的锁，是在查看listCollections的官方文档时。文档是这样写的
The listCollections command takes Intent Shared lock on the database. In previous versions, the command takes Shared lock on the database.
Unless the nameOnly option is specified, the command also takes an Intent Shared lock on each of the collections in turn while holding the Intent Shared lock on the database.
不禁好奇，Intent Shared lock指的是什么，Shared lock指的又是什么，有什么不同？
标签：takes,database,lock,command,第七篇,Intent,mongodb,Shared From： https://www.cnblogs.com/koushr/p/17137659.html