using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using SqlSugar;
using NewTest.Dao;
using Models;
using System.Data.SqlClient;
using System.Data;
namespace NewTest.Demos
{
//查询的例子
public class Select : IDemos
{
public void Init()
{
Console.WriteLine("启动Select.Init");
//使用拉姆达查询 基于Queryable
QueryableDemo();
//新容器转换
QueryableSelectNewClass();
//使用更接近sql的查询方式 基于Sqlable
SqlableDemo();
//使用原生Sql查询
SqlQuery();
}
/// <summary>
/// 拉姆达表达示
/// </summary>
private void QueryableDemo()
{
using (var db = SugarDao.GetInstance())
{
db.IsNoLock = true;
//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);
//查询单条根据主键
var singleByPk = db.Queryable<Student>().InSingle(1);
//查询单条没有记录返回空对象
var singleOrDefault = db.Queryable<Student>().SingleOrDefault(c => c.id == 11111111);
//查询单条没有记录返回空对象
var single2 = db.Queryable<Student>().Where(c => c.id == 1).SingleOrDefault();
//查询所有的Id
var singleFieldList = db.Queryable<Student>().Select<int>(it=>it.id).ToList();
//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11-20条
var page1 = db.Queryable<Student>().Where(c => c.id > 10).OrderBy(it => it.id).Skip(10).Take(10).ToList();
//取11-20条 等于 Skip(pageIndex-1)*pageSize).Take(pageSize) 等于 between (pageIndex-1)*pageSize and pageIndex*pageSize
var page2 = db.Queryable<Student>().Where(c => c.id > 10).OrderBy(it => it.id).ToPageList(2, 10);
//取11-20条并且返回PageCount
int pageCount = 0;
var page3 = db.Queryable<Student>().Where(c => c.id > 10).OrderBy(it => it.id).ToPageList(2, 10, ref pageCount);
//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();
//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>@id", new { id = 1 }).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<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<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 listnew = db.Queryable<Student>().Where(it => intArray.Contains(it.name)).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();
var list6 = db.Queryable<Student>().In(intList).ToList();//不设置字段默认主键
//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<StudentGroup> list9 = db.Queryable<Student>().Where(c => c.id < 20).GroupBy(it => it.sex).Select<StudentGroup>("Sex,count(*) Count").ToList();
List<StudentGroup> list10 = db.Queryable<Student>().Where(c => c.id < 20).GroupBy("sex").Select<StudentGroup>("Sex,count(*) Count").ToList();
//SELECT Sex,Count=count(*) FROM Student WHERE 1=1 AND (id < 20) GROUP BY Sex --生成结果
//2表关联查询
var jList = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id) //默认left join
.Where<School>((s1, s2) => s1.id == 1)
.Select("s1.*,s2.name as schName")
.ToDynamic();
/*等于同于
SELECT s1.*,s2.name as schName
FROM [Student] s1
LEFT JOIN [School] s2 ON s1.sch_id = s2.id
WHERE s1.id = 1 */
//2表关联查询并分页
var jList2 = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id) //默认left join
//如果要用inner join这么写
//.JoinTable<School>((s1, s2) => s1.sch_id == s2.id ,JoinType.INNER)
.Where<School>((s1, s2) => s1.id > 1)
.OrderBy(s1 => s1.name)
.Skip(10)
.Take(20)
.Select("s1.*,s2.name as schName")
.ToDynamic();
//3表查询并分页
var jList3 = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id) // left join School s2 on s1.id=s2.id
.JoinTable<School>((s1, s3) => s1.sch_id == s3.id) // left join School s3 on s1.id=s3.id
.Where<School>((s1, s2) => s1.id > 1) // where s1.id>1
.Where(s1 => s1.id > 0)
.OrderBy<School>((s1, s2) => s1.id) //order by s1.id 多个order可以 .oderBy().orderby 叠加
.Skip(10)
.Take(20)
.Select("s1.*,s2.name as schName,s3.name as schName2");//select目前只支持这种写法
//.ToDynamic();
//上面的方式都是与第一张表join，第三张表想与第二张表join写法如下
List<V_Student> jList4 =
db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id) // left join School s2 on s1.id=s2.id
.JoinTable<School, Area>((s1, s2, a1) => a1.id == s2.AreaId)// left join Area a1 on a1.id=s2.AreaId 第三张表与第二张表关联
.JoinTable<Area, School>((s1, a1, s3) => a1.id == s3.AreaId)// left join School s3 on a1.id=s3.AreaId 第四第表第三张表关联
.JoinTable<School>((s1, s4) => s1.sch_id == s4.id) // left join School s2 on s1.id=s4.id
.Select<School, Area, V_Student>((s1, s2, a1) => new V_Student { id = s1.id, name = s1.name, SchoolName = s2.name, AreaName = a1.name }).ToList();
//等同于
//SELECT id = s1.id, name = s1.name, SchoolName = s2.name, AreaName = a1.name
//FROM [Student] s1
//LEFT JOIN School s2 ON ( s1.sch_id = s2.id )
//LEFT JOIN Area a1 ON ( a1.id = s2.AreaId ) //第三张表与第二张表关联
//LEFT JOIN School s3 ON ( a1.id = s3.AreaId ) //第四张表与第三张表关联
//LEFT JOIN School s4 ON ( s1.sch_id = s4.id )
//WHERE 1=1
//Join子查询语句加分页的写法
var childQuery = db.Queryable<Area>().Where("id=@id").Select(it => new { id = it.id,name=it.name }).ToSql();//创建子查询SQL
string childTableName =SqlSugarTool.PackagingSQL(childQuery.Key);//将SQL语句用()包成表
var queryable = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id) //LEFT JOIN School s2 ON ( s1.sch_id = s2.id )
.JoinTable(childTableName, "a1", "a1.id=s2.areaid", new { id = 1 }, JoinType.Inner) //INNER JOIN (SELECT * FROM [Area] WHERE 1=1 AND id=@id ) a1 ON a1.id=s2.areaid
.OrderBy(s1 => s1.id);
var list = queryable.Select<School, Area, V_Student>((s1, s2, a1) => new V_Student { id = s1.id, name = s1.name, SchoolName = s2.name, AreaName = a1.name })
.ToPageList(0, 200);
var count2 = queryable.Count();
//拼接例子
var queryable2 = db.Queryable<Student>().Where(it => true);
if (maxId.ObjToInt() == 1)
{
queryable2.Where(it => it.id == 1);
}
else
{
queryable2.Where(it => it.id == 2);
}
var listJoin = queryable2.ToList();
//queryable和SqlSugarClient解耦
var par = new Queryable<Student>().Where(it => it.id == 1);//声名没有connection对象的Queryable
par.DB = db;
var listPar = par.ToList();
//查看生成的sql和参数
var id = 1;
var sqlAndPars = db.Queryable<Student>().Where(it => it.id == id).OrderBy(it => it.id).ToSql();
//拉姆达支持的函数操作
var par1 = "2015-1-1"; var par2 = " 我 有空格A, ";
var r1 = db.Queryable<Student>().Where(it => it.name == par1.ObjToString()).ToList(); //ObjToString会将null转转成""
var r2 = db.Queryable<InsertTest>().Where(it => it.d1 == par1.ObjToDate()).ToList();
var r3 = db.Queryable<InsertTest>().Where(it => it.id == 1.ObjToInt()).ToList();//ObjToInt会将null转转成0
var r4 = db.Queryable<InsertTest>().Where(it => it.id == 2.ObjToDecimal()).ToList();
var r5 = db.Queryable<InsertTest>().Where(it => it.id == 3.ObjToMoney()).ToList();
var r6 = db.Queryable<InsertTest>().Where(it => it.v1 == par2.Trim()).ToList();
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 => c.name == par2.ToLower()).ToList();
var convert4 = db.Queryable<Student>().Where(c => c.name == par2.ToUpper()).ToList();
var convert5= db.Queryable<Student>().Where(c => DateTime.Now > Convert.ToDateTime("2015-1-1")).ToList();
var c1 = db.Queryable<Student>().Where(c => c.name.Contains("a")).ToList();
var c2 = db.Queryable<Student>().Where(c => c.name.StartsWith("a")).ToList();
var c3 = db.Queryable<Student>().Where(c => c.name.EndsWith("a")).ToList();
var c4 = db.Queryable<Student>().Where(c => !string.IsNullOrEmpty(c.name)).ToList();
var c5 = db.Queryable<Student>().Where(c => c.name.Equals("小杰")).ToList();
var c6 = db.Queryable<Student>().Where(c => c.name.Length > 4).ToList();
var time = db.Queryable<InsertTest>().Where(c => c.d1>DateTime.Now.AddDays(1)).ToList();
var time2 = db.Queryable<InsertTest>().Where(c => c.d1 > DateTime.Now.AddYears(1)).ToList();
var time3 = db.Queryable<InsertTest>().Where(c => c.d1 > DateTime.Now.AddMonths(1)).ToList();
}
}
/// <summary>
/// 新容器转换
/// </summary>
private void QueryableSelectNewClass()
{
using (SqlSugarClient db = SugarDao.GetInstance())
{
//单表操作将Student转换成V_Student
var queryable = db.Queryable<Student>().Where(c => c.id < 10)
.Select<V_Student>(c => new V_Student { id = c.id, name = c.name, AreaName = "默认地区", SchoolName = "默认学校", SubjectName = "NET" });
var list = queryable.ToList();
var list4 = db.Queryable<Student>().Where(c => c.id < 10)
.Select<V_Student>(c => new V_Student { id = c.id, name = c.name, AreaName = "默认地区", SchoolName = "默认学校", SubjectName = "NET" }).First();
//多表操作将Student转换成V_Student
var queryable2 = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id)
.Where<School>((s1, s2) => s2.id < 10)
.Select<School, V_Student>((s1, s2) => new V_Student() { id = s1.id, name = s1.name, AreaName = "默认地区", SchoolName = s2.name, SubjectName = "NET" });//select new 目前只支持这种写法
var list2 = queryable2.ToList();
var json2 = queryable2.ToJson();
var dynamic2 = queryable2.ToDynamic();
//select字符串 转换成V_Student
var list3 = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id)
.Where(s1 => s1.id <= 3)
.Select<V_Student>("s1.*,s2.name SchoolName")
.ToList();
//select字符串 转换成Json
var json3 = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id)
.Where(s1 => s1.id <= 3)
.Select<V_Student>("s1.*,s2.name SchoolName");
//.ToJson();
//select字符串 转换成Json
var dynamic3 = db.Queryable<Student>()
.JoinTable<School>((s1, s2) => s1.sch_id == s2.id,JoinType.Left)
.Where(s1 => s1.id <= 3)
.Select<V_Student>("s1.*,s2.name SchoolName")
.ToDynamic();
//新容器转换函数的支持 只支持ObjToXXX和Convert.ToXXX
var f1 = db.Queryable<InsertTest>().Select<Student>(it => new Student()
{
name = it.d1.ObjToString(),
id = it.int1.ObjToInt() // 支持ObjToXXX 所有函数
}).ToList();
var f2 = db.Queryable<InsertTest>().Select<Student>(it => new Student()
{
name = Convert.ToString(it.d1),//支持Convet.ToXX所有函数
id = it.int1.ObjToInt(),
sex = Convert.ToString(it.d1),
}).ToList();
var f3 = db.Queryable<InsertTest>()
.JoinTable<InsertTest>((i1, i2) => i1.id == i2.id)
.Select<InsertTest, Student>((i1, i2) => new Student()
{
name = Convert.ToString(i1.d1), //多表查询例子
id = i1.int1.ObjToInt(),
sex = Convert.ToString(i2.d1),
}).ToList();
//Select 外部参数用法
var f4 = db.Queryable<InsertTest>().Where("1=1", new { id = 100 }).Select<Student>(it => new Student()
{
id = "@id".ObjToInt(), //取的是 100 的值
name = "张三",//内部参数可以直接写
sex = it.txt,
sch_id = it.id
}).ToList();
var f6 = db.Queryable<InsertTest>()
.JoinTable<InsertTest>((i1, i2) => i1.id == i2.id)
.Where("1=1", new { id = 100, name = "张三", isOk = true }) //外部传参给@id
.Select<InsertTest, Student>((i1, i2) => new Student()
{
name = "@name".ObjToString(), //多表查询例子
id = "@id".ObjToInt(),
sex = i2.txt,
sch_id = 1,
isOk = "@isOk".ObjToBool()
}).ToList();
}
}
/// <summary>
/// 基于原生Sql的查询
/// </summary>
private void SqlQuery()
{
using (var db = SugarDao.GetInstance())
{
//转成list
List<Student> list1 = db.SqlQuery<Student>("select * from Student");
//转成list带参
List<Student> list2 = db.SqlQuery<Student>("select * from Student where id=@id", new { id = 1 });
//转成dynamic
dynamic list3 = db.SqlQueryDynamic("select * from student");
//转成json
string list4 = db.SqlQueryJson("select * from student");
//返回int
var list5 = db.SqlQuery<int>("select top 1 id from Student").SingleOrDefault();
//反回键值
Dictionary<string, string> list6 = db.SqlQuery<KeyValuePair<string, string>>("select id,name from Student").ToDictionary(it => it.Key, it => it.Value);
//反回List<string[]>
var list7 = db.SqlQuery<string[]>("select top 1 id,name from Student").SingleOrDefault();
//存储过程
var spResult = db.SqlQuery<School>("exec sp_school @p1,@p2", new { p1 = 1, p2 = 2 });
//存储过程加Output
var pars = SqlSugarTool.GetParameters(new { p1 = 1,p2=0 }); //将匿名对象转成SqlParameter
db.IsClearParameters = false;//禁止清除参数
pars[1].Direction = ParameterDirection.Output; //将p2设为 output
var spResult2 = db.SqlQuery<School>("exec sp_school @p1,@p2 output", pars);
db.IsClearParameters = true;//启用清除参数
var outPutValue = pars[1].Value;//获取output @p2的值
//存储过程优化操作
var pars2 = SqlSugarTool.GetParameters(new { p1 = 1, p2 = 0 }); //将匿名对象转成SqlParameter
db.CommandType = CommandType.StoredProcedure;//指定为存储过程可比上面少写EXEC和参数
var spResult3 = db.SqlQuery<School>("sp_school", pars2);
db.CommandType = CommandType.Text;//还原回默认
//获取第一行第一列的值
string v1 = db.GetString("select '张三' as name");
int v2 = db.GetInt("select 1 as name");
double v3 = db.GetDouble("select 1 as name");
decimal v4 = db.GetDecimal("select 1 as name");
//....
}
}
/// <summary>
/// 接近Sql的编程模式
/// </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
.OrderBy("id")
.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);
}
}
}
}
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