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  • Mongodb 与sql 语句对照

      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’
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  • 原文地址:https://www.cnblogs.com/qq75077027/p/2834740.html
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