/Files/hanguoji/MongoDB权威指南中文版.rar

MongoDB权威介绍：http://www.cnblogs.com/silentcross/archive/2011/06/27/2091530.html

查询：
MySQL:
SELECT * FROM user
Mongo:
db.user.find()

MySQL:
SELECT * FROM user WHERE name = ’starlee’
Mongo:
db.user.find({‘name’ : ’starlee’})

插入：
MySQL:
INSERT INOT user (`name`, `age`) values (’starlee’,25)
Mongo:
db.user.insert({‘name’ : ’starlee’, ‘age’ : 25})

如果你想在MySQL里添加一个字段，你必须：
ALTER TABLE user….
但在MongoDB里你只需要：
db.user.insert({‘name’ : ’starlee’, ‘age’ : 25, ‘email’ : ’starlee@starlee.com’})

删除：
MySQL:
DELETE * FROM user
Mongo:
db.user.remove({})

MySQL:
DELETE FROM user WHERE age < 30
Mongo:
db.user.remove({‘age’ : {$lt : 30}})

$gt : > ; $gte : >= ; $lt : < ; $lte : <= ; $ne : !=

更新:

MySQL:
UPDATE user SET `age` = 36 WHERE `name` = ’starlee’
Mongo:
db.user.update({‘name’ : ’starlee’}, {$set : {‘age’ : 36}})

MySQL:
UPDATE user SET `age` = `age` + 3 WHERE `name` = ’starlee’
Mongo:
db.user.update({‘name’ : ’starlee’}, {$inc : {‘age’ : 3}})

MySQL:
SELECT COUNT(*) FROM user WHERE `name` = ’starlee’
Mongo:
db.user.find({‘name’ : ’starlee’}).count()

MySQL:
SELECT * FROM user limit 10,20
Mongo:
db.user.find().skip(10).limit(20)

MySQL:
SELECT * FROM user WHERE `age` IN (25, 35,45)
Mongo:
db.user.find({‘age’ : {$in : [25, 35, 45]}})

MySQL:
SELECT * FROM user ORDER BY age DESC
Mongo:
db.user.find().sort({‘age’ : -1})

MySQL:
SELECT DISTINCT(name) FROM user WHERE age > 20
Mongo:
db.user.distinct(‘name’, {‘age’: {$lt : 20}})

MySQL:
SELECT name, sum(marks) FROM user GROUP BY name
Mongo:
db.user.group({
key : {‘name’ : true},
cond: {‘name’ : ‘foo’},
reduce: function(obj,prev) { prev.msum += obj.marks; },
initial: {msum : 0}
});

MySQL:
SELECT name FROM user WHERE age < 20
Mongo:
db.user.find(‘this.age < 20′, {name : 1})

MongoDB循环插入数据：

for(var i=0;i<100;i++)db.test.insert({uid:i,uname:’nosqlfan’+i});

上面一次性插入一百条数据，大概结构如下：

{ “_id” : ObjectId(“4c876e519e86023a30dde6b8″), “uid” : 55, “uname” : “nosqlfan55″ }

{ “_id” : ObjectId(“4c876e519e86023a30dde6b9″), “uid” : 56, “uname” : “nosqlfan56″ }

{ “_id” : ObjectId(“4c876e519e86023a30dde6ba”), “uid” : 57, “uname” : “nosqlfan57″ }

{ “_id” : ObjectId(“4c876e519e86023a30dde6bb”), “uid” : 58, “uname” : “nosqlfan58″ }

{ “_id” : ObjectId(“4c876e519e86023a30dde6bc”), “uid” : 59, “uname” : “nosqlfan59″ }

{ “_id” : ObjectId(“4c876e519e86023a30dde6bd”), “uid” : 60, “uname” : “nosqlfan60″ }