陈乔恩上节目脱内衣:Mongodb 与sql 语句对照

Mongodb 与sql 语句对照
此处用mysql中的sql语句做例子,C# 驱动用的是samus,也就是上文中介绍的第一种.
引入项目MongoDB.dll
//创建Mongo连接 var mongo = new Mongo("mongodb://localhost"); mongo.Connect(); //获取一个数据库,如果没有会自动创建一个 var db = mongo.GetDatabase("movieReviews"); //创建一个列表,并为这个列表创建文档 var movies = db.GetCollection("movies");
连接没问题之后,现在让我们用mysql 与mongodb的一些语句做下对比:
MongoDB Mysql
查询全部 movies.find(new Document()) SELECT * FROM movies
条件查询 movies.Find(new Document { { "title", "Hello Esr" } }); SELECT * FROM movies WHERE title= 'foobar'
查询数量 movies.Find(new Document { { "title", "测试2" } }).Documents.Count(); SELECT COUNT(*) FROM movies WHERE `title` = 'foobar'
数量范围查询 1, movies.Find(new Document().Add("$where", new Code("this.num > 50")));
2, movies.Find(new Document().Add("num",  new Document().Add("$gt",50)));
($gt : > ; $gte : >= ; $lt : < ; $lte : <= ; $ne : !=)
3,movies.Find("this.num > 50");
4,movies.Find(new Document().Add("$where",new Code("function(x){ return this.num > 50};"))); select * from movies where num > 50
分页查询 movies.Find(new Document()).Skip(10).Limit(20); SELECT * FROM movies  limit 10,20
查询排序语句 movies.Find(new Document()).Sort(new Document() { { "num", -1 } }); SELECT * FROM movies ORDER BY num DESC
查询指定字段 movies.Find(new Document().Add("num", new Document().Add("$gt", 50)), 10, 0, new Document() { { "title", 1 } }); select title from movies where num > 50
插入语句 movies.Insert(new Document() { { "title", "测试" }, { "resuleData", DateTime.Now } }); INSERT INOT movies (`title`, `reauleDate`) values ('foobar',25)
删除语句 movies.Remove(new Document() { { "title", "Hello Esr" } }); DELETE * FROM movies
更新语句
movies.Update(new Document() { { "title", "测试2" } }
, new Document() { { "title", "测试11111" } });
UPDATE movies SET `title` = ‘测试1111’ WHERE `title` = '测试1111'
Linq查询
(from item in db.GetCollection("movies").Linq()
where ((string)item["title"]).StartsWith("Esr")
select item);
select * from movies where title like ‘%Esr’
这里只举出了几个比较典型的例子,可以这么说,只要mysql可以完成的sql语句,在mongodb里面都可以实现.