MongoDB插入查询数据(二)， 条件查询

db.things.find({name:"mongo" }).forEach(printjson);{ "_id" : ObjectId("501c7e5cab2f3c46faf8e68a"), "name" : "mongo" } 相当于 SELECT * FROM things WHERE . 里指定元素的名字 SELECT name FROM things WHERE db.things.find({name:"mongo"}, {name:

> db.things.find({name:"mongo"}).forEach(printjson); { "_id" : ObjectId("501c7e5cab2f3c46faf8e68a"), "name" : "mongo" }

相当于SELECT * FROM things WHERE

…”.

里指定元素的名字

SELECT name FROM things WHERE

> db.things.find({name:"mongo"}, {name:true}).forEach(printjson); { "_id" : ObjectId("501c7e5cab2f3c46faf8e68a"), "name" : "mongo" }

方法.

> db.things.find().limit(2); { "_id" : ObjectId("501c7e5cab2f3c46faf8e68a"), "name" : "mongo" } { "_id" : ObjectId("501c7e65ab2f3c46faf8e68b"), "x" : 3 }