/// <summary> /// 单表查询 /// </summary> private void QueryableDemo() { using (var db = SugarDao.GetInstance()) { //---------Queryable<T>,扩展函数查询---------// //针对单表或者视图查询 //查询所有 var student = db.Queryable <Student>().ToList(); var studentDynamic = db.Queryable <Student>().ToDynamic(); var studentJson = db.Queryable <Student>().ToJson(); //查询单条 var single = db.Queryable <Student>().Single(c => c.id == 1); //查询单条没有记录返回空对象 var single2 = db.Queryable <Student>().Where(c => c.id == 1).SingleOrDefault(); //查询第一条 var first = db.Queryable <Student>().Where(c => c.id == 1).First(); var first2 = db.Queryable <Student>().Where(c => c.id == 1).FirstOrDefault(); //取10-20条 var page1 = db.Queryable <Student>().Where(c => c.id > 10).OrderBy("id").Skip(10).Take(20).ToList(); //上一句的简化写法,同样取10-20条 var page2 = db.Queryable <Student>().Where(c => c.id > 10).OrderBy("id").ToPageList(2, 10); //查询条数 var count = db.Queryable <Student>().Where(c => c.id > 10).Count(); //从第2条开始以后取所有 var skip = db.Queryable <Student>().Where(c => c.id > 10).OrderBy("id").Skip(2).ToList(); //取前2条 var take = db.Queryable <Student>().Where(c => c.id > 10).OrderBy("id").Take(2).ToList(); // Not like string conval = "a"; var notLike = db.Queryable <Student>().Where(c => !c.name.Contains(conval.ToString())).ToList(); //Like conval = "三"; var like = db.Queryable <Student>().Where(c => c.name.Contains(conval)).ToList(); // 可以在拉姆达使用 ToString和 Convert,比EF出色的地方 var convert1 = db.Queryable <Student>().Where(c => c.name == "a".ToString()).ToList(); var convert2 = db.Queryable <Student>().Where(c => c.id == Convert.ToInt32("1")).ToList();// var convert3 = db.Queryable <Student>().Where(c => DateTime.Now > Convert.ToDateTime("2015-1-1")).ToList(); var convert4 = db.Queryable <Student>().Where(c => DateTime.Now > DateTime.Now).ToList(); //支持字符串Where 让你解决,更复杂的查询 var student12 = db.Queryable <Student>().Where(c => "a" == "a").Where("id>100").ToList(); var student13 = db.Queryable <Student>().Where(c => "a" == "a").Where("id>100 and id in( select 1)").ToList(); //存在记录反回true,则否返回false bool isAny100 = db.Queryable <Student>().Any(c => c.id == 100); bool isAny1 = db.Queryable <Student>().Any(c => c.id == 1); int maxId = db.Queryable <Student>().Max <Student, int>("id"); int minId = db.Queryable <Student>().Where(c => c.id > 0).Min <Student, int>("id"); //In var list1 = db.Queryable <Student>().In("id", "1", "2", "3").ToList(); var list2 = db.Queryable <Student>().In("id", new string[] { "1", "2", "3" }).ToList(); var list3 = db.Queryable <Student>().In("id", new List <string> { "1", "2", "3" }).ToList(); var list4 = db.Queryable <Student>().Where(it => it.id < 10).In("id", new List <string> { "1", "2", "3" }).ToList(); //分组查询 var list5 = db.Queryable <Student>().Where(c => c.id < 20).GroupBy("sex").Select <Student, SexTotal>("Sex,Count=count(*)").ToList(); //SELECT Sex,Count=count(*) FROM Student WHERE 1=1 AND (id < 20) GROUP BY Sex --生成结果 } }
/// <summary> /// 多表查询 /// </summary> private void SqlableDemo() { using (var db = SugarDao.GetInstance()) { //---------Sqlable,创建多表查询---------// //多表查询 List <School> dataList = db.Sqlable() .From("school", "s") .Join("student", "st", "st.id", "s.id", JoinType.INNER) .Join("student", "st2", "st2.id", "st.id", JoinType.LEFT) .Where("s.id>100 and s.id<@id") .Where("1=1")//可以多个WHERE .SelectToList <School /*新的Model我这里没有所以写的School*/>("st.*", new { id = 1 }); //多表分页 List <School> dataPageList = db.Sqlable() .From("school", "s") .Join("student", "st", "st.id", "s.id", JoinType.INNER) .Join("student", "st2", "st2.id", "st.id", JoinType.LEFT) .Where("s.id>100 and s.id<100") .SelectToPageList <School>("st.*", "s.id", 1, 10); //多表分页WHERE加子查询 List <School> dataPageList2 = db.Sqlable() .From("school", "s") .Join("student", "st", "st.id", "s.id", JoinType.INNER) .Join("student", "st2", "st2.id", "st.id", JoinType.LEFT) .Where("s.id>100 and s.id<100 and s.id in (select 1 )" /*这里面写子查询都可以*/) .SelectToPageList <School>("st.*", "s.id", 1, 10); //--------转成List Dynmaic 或者 Json-----// //不分页 var list1 = db.Sqlable().From("student", "s").Join("school", "l", "s.sch_id", "l.id and l.id=@id", JoinType.INNER).SelectToDynamic("*", new { id = 1 }); var list2 = db.Sqlable().From("student", "s").Join("school", "l", "s.sch_id", "l.id and l.id=@id", JoinType.INNER).SelectToJson("*", new { id = 1 }); var list3 = db.Sqlable().From("student", "s").Join("school", "l", "s.sch_id", "l.id and l.id=@id", JoinType.INNER).SelectToDataTable("*", new { id = 1 }); //分页 var list4 = db.Sqlable().From("student", "s").Join("school", "l", "s.sch_id", "l.id and l.id=@id", JoinType.INNER).SelectToPageDynamic("s.*", "l.id", 1, 10, new { id = 1 }); var list5 = db.Sqlable().From("student", "s").Join("school", "l", "s.sch_id", "l.id and l.id=@id", JoinType.INNER).SelectToPageTable("s.*", "l.id", 1, 10, new { id = 1 }); var list6 = db.Sqlable().From("student", "s").Join("school", "l", "s.sch_id", "l.id and l.id=@id", JoinType.INNER).SelectToPageDynamic("s.*", "l.id", 1, 10, new { id = 1 }); //--------拼接-----// Sqlable sable = db.Sqlable().From <Student>("s").Join <School>("l", "s.sch_id", "l.id", JoinType.INNER); string name = "a"; int id = 1; if (!string.IsNullOrEmpty(name)) { sable = sable.Where("s.name=@name"); } if (!string.IsNullOrEmpty(name)) { sable = sable.Where("s.id=@id or s.id=100"); } if (id > 0) { sable = sable.Where("l.id in (select top 10 id from school)");//where加子查询 } var pars = new { id = id, name = name }; int pageCount = sable.Count(pars); var list7 = sable.SelectToPageList <Student>("s.*", "l.id desc", 1, 20, pars); } }
/// <summary> /// 单表查询 /// </summary> private void QueryableDemo() { using (var db = SugarDao.GetInstance()) { //---------Queryable<T>,扩展函数查询---------// //针对单表或者视图查询 //查询所有 var student = db.Queryable <Student>().ToList(); var studentDynamic = db.Queryable <Student>().ToDynamic(); var studentJson = db.Queryable <Student>().ToJson(); //查询单条 var single = db.Queryable <Student>().Single(c => c.id == 1); //查询单条没有记录返回空对象 var single2 = db.Queryable <Student>().Where(c => c.id == 1).SingleOrDefault(); //查询第一条 var first = db.Queryable <Student>().Where(c => c.id == 1).First(); var first2 = db.Queryable <Student>().Where(c => c.id == 1).FirstOrDefault(); //取10-20条 var page1 = db.Queryable <Student>().Where(c => c.id > 10).OrderBy(it => it.id).Skip(10).Take(20).ToList(); //上一句的简化写法,同样取10-20条 var page2 = db.Queryable <Student>().Where(c => c.id > 10).OrderBy(it => it.id).ToPageList(2, 10); //查询条数 var count = db.Queryable <Student>().Where(c => c.id > 10).Count(); //从第2条开始以后取所有 var skip = db.Queryable <Student>().Where(c => c.id > 10).OrderBy(it => it.id).Skip(2).ToList(); //取前2条 var take = db.Queryable <Student>().Where(c => c.id > 10).OrderBy(it => it.id).Take(2).ToList(); // Not like string conval = "a"; var notLike = db.Queryable <Student>().Where(c => !c.name.Contains(conval.ToString())).ToList(); //Like conval = "三"; var like = db.Queryable <Student>().Where(c => c.name.Contains(conval)).ToList(); // 可以在拉姆达使用 ToString和 Convert,比EF出色的地方 var convert1 = db.Queryable <Student>().Where(c => c.name == "a".ToString()).ToList(); var convert2 = db.Queryable <Student>().Where(c => c.id == Convert.ToInt32("1")).ToList();// var convert3 = db.Queryable <Student>().Where(c => DateTime.Now > Convert.ToDateTime("2015-1-1")).ToList(); var convert4 = db.Queryable <Student>().Where(c => DateTime.Now > DateTime.Now).ToList(); //支持字符串Where 让你解决,更复杂的查询 var student12 = db.Queryable <Student>().Where(c => "a" == "a").Where("id>100").ToList(); var student13 = db.Queryable <Student>().Where(c => "a" == "a").Where("id>100 and id in( select 1)").ToList(); //存在记录反回true,则否返回false bool isAny100 = db.Queryable <Student>().Any(c => c.id == 100); bool isAny1 = db.Queryable <Student>().Any(c => c.id == 1); //获取最大Id object maxId = db.Queryable <Student>().Max(it => it.id); int maxId1 = db.Queryable <Student>().Max(it => it.id).ObjToInt(); //拉姆达 int maxId2 = db.Queryable <Student>().Max <Student, int>("id"); //字符串写法 //获取最小 int minId1 = db.Queryable <Student>().Where(c => c.id > 0).Min(it => it.id).ObjToInt(); //拉姆达 int minId2 = db.Queryable <Student>().Where(c => c.id > 0).Min <Student, int>("id"); //字符串写法 //order By var orderList = db.Queryable <Student>().OrderBy("id desc,name asc").ToList(); //字符串支持多个排序 //可以多个order by表达示 var order2List = db.Queryable <Student>().OrderBy(it => it.name).OrderBy(it => it.id, OrderByType.desc).ToList(); // order by name as ,order by id desc //In var intArray = new[] { "5", "2", "3" }; var intList = intArray.ToList(); var list0 = db.Queryable <Student>().In(it => it.id, 1, 2, 3).ToList(); var list1 = db.Queryable <Student>().In(it => it.id, intArray).ToList(); var list2 = db.Queryable <Student>().In("id", intArray).ToList(); var list3 = db.Queryable <Student>().In(it => it.id, intList).ToList(); var list4 = db.Queryable <Student>().In("id", intList).ToList(); //分组查询 var list7 = db.Queryable <Student>().Where(c => c.id < 20).GroupBy(it => it.sex).Select("sex,Count=count(*)").ToDynamic(); var list8 = db.Queryable <Student>().Where(c => c.id < 20).GroupBy(it => it.sex).GroupBy(it => it.id).Select("id,sex,Count=count(*)").ToDynamic(); List <SexTotal> list9 = db.Queryable <Student>().Where(c => c.id < 20).GroupBy(it => it.sex).Select <Student, SexTotal>("Sex,Count=count(*)").ToList(); List <SexTotal> list10 = db.Queryable <Student>().Where(c => c.id < 20).GroupBy("sex").Select <Student, SexTotal>("Sex,Count=count(*)").ToList(); //SELECT Sex,Count=count(*) FROM Student WHERE 1=1 AND (id < 20) GROUP BY Sex --生成结果 } }