• MongoDB的命令行语句,也可以引用插件LINQ的形式应用


     /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″ }
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  • 原文地址:https://www.cnblogs.com/hanguoji/p/2749458.html
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