介绍一种新类型查询方法,类似linq,lambda语法,类似标准的sql使用习惯,支持匿名类型,泛型,目前支持mssql,mysql,
切换只需要DatabaseConfig.DatabaseType = DatabaseType.SQLServer;无需改任何代码,dll后续开放下载
使用说明:基于实体查询,实体名和表名相同,实体需要使用代码生成器生成,工具后续开放下载
只需要生成所有表的实体,其它数据任意查,不需要手写任何Model,
查询结果
1 public class Student
2 {
3 public int ID { get; set; }
4 public string Name { get; set; }
5 public int Age { get; set; }
6 public bool IsGraduate { get; set; }
7 public string Grade { get; set; }
8 public decimal Money { get; set; }
9 }
表对应实体
1 /// <summary>
2 /// 单表查询
3 /// </summary>
4 public static void single_able()
5 {
6 using (var sql = new SqlModel<T_BAS_Areas>())
7 {
8 //!+常用方法
9 /*
10 *使用说明
11 *数据查询方法,只有调用后才会有数据返回
12 *ToDataTable(),ToList(),ToPageList(),First(),FirstOrDefault()
13 */
14 //?查默认一条数据
15 var data1 = sql
16 .SqlSelect(a => new { a.AreaName, a.AreaCode })
17 .FirstOrDefault();
18 //?所有字段查询
19 var data1_1 = sql
20 .SqlSelect()
21 .FirstOrDefault();
22 //查询top 10
23 var data1_2 = sql
24 .SqlSelect()
25 .SqlTop(10)
26 .ToList();
27 //?DataTable
28 var data2 = sql
29 .SqlSelect(a => new { a.AreaName, a.AreaCode })
30 .ToDataTable();
31 //?List
32 var data3 = sql
33 .SqlSelect(a => new { a.AreaName, a.AreaCode })
34 .ToList();
35 //?分页
36 var data4 = sql
37 .SqlPage(a => new { a.AreaName, a.AreaCode })
38 .ToPageList();
39 var data4_1 = sql
40 .SqlPage(a => new { a.AreaName, a.AreaCode }, 1, 20)
41 .ToPageList();
42 //?count
43 var data5 = sql
44 .SqlCount(a => a.AreaCode == "");
45 //?sum
46 var data6 = sql
47 .SqlSum(a => new { a.AreaCode })
48 .First();
49
50 //?无锁查询
51 var data7 = sql
52 .SqlSelect(a => new { a.AreaName, a.AreaCode }, LockType.NOLOCK)
53 .FirstOrDefault();
54 //?指定索引查询
55 var data8 = sql
56 .SqlSelect(a => new { a.AreaName, a.AreaCode }
57 , "PK_T_BAS_AREAS")
58 .FirstOrDefault();
59
60 //?条件查询
61 var data9 = sql
62 .SqlSelect(a => new { a.AreaName, a.AreaCode })
63 .SqlWhere(a => a.ParentAreaCode == "1251" && a.AreaName.SqlLike("九江"))
64 .FirstOrDefault();
65 //? 查前10条并排序
66 var data10 = sql
67 .SqlSelect(a => new { a.AreaName, a.ParentAreaCode, a.AreaCode })
68 .SqlTop(10)
69 .SqlOrderBy(b => new { b.ParentAreaCode, b.AreaCode })
70 .ToList();
71 var data11 = sql
72 .SqlSelect(a => new { a.AreaName, a.ParentAreaCode, a.AreaCode })
73 .SqlTop(10)
74 .SqlOrderDescBy(b => new { b.ParentAreaCode, b.AreaCode })
75 .ToList();
76 //? 查前10%条并排序
77 var data12 = sql
78 .SqlSelect(a => new { a.AreaName, a.ParentAreaCode, a.AreaCode })
79 .SqlPercent(10).SqlOrderBy(b => new { b.ParentAreaCode }).ToList();
80 data12 = sql.SqlSelect(a => new { a.AreaName, a.ParentAreaCode, a.AreaCode })
81 .SqlPercent(10)
82 .SqlOrderDescBy(b => new { b.ParentAreaCode })
83 .SqlOrderBy(c => new { c.AreaCode })
84 .ToList();
85
86 //?查前10条不重复的项
87 var data13 = sql
88 .SqlSelect(a => new { a.ParentAreaCode, a.AreaCode })
89 .SqlDistinct()
90 .SqlTop(10)
91 .ToList();
92
93 //!更新
94 sql.SqlUpdate(a => new object[] { a.AreaName == "溪湖区" },//a.SqlFunc("AreaCode=‘2‘")
95 b => b.AreaGuidGuid == Guid.Parse("949B2F9D-F730-48ED-8B58-000144166BE9"));
96
97
98 //!添加
99 T_BAS_Areas area = new T_BAS_Areas()
100 {
101 AreaGuidGuid = Guid.NewGuid(),
102 AreaCode = "1",
103 AreaName = "测试",
104 ParentAreaCode = "-1",
105 };
106 sql.SqlAdd(area);
107 //!删除
108 sql.SqlDelete(a => a.AreaGuidGuid == area.AreaGuidGuid);
109
110 //where 查询
111 var data14 = sql
112 .SqlSelect(a => new { a.AreaName, a.AreaCode })
113 .SqlWhere(a => a.AreaName.SqlLike("六一") && a.AreaCode.SqlFunc("AreaCode=1"))
114 .ToList();
115 var data141 = sql
116 .SqlSelect(a => new { a.AreaName, a.AreaCode })
117 .SqlWhere(a => a.AreaName.SqlLike("%{0}?", "六一")
118 && a.AreaCode.SqlFunc("AreaCode=‘1‘")//a.SqlFunc("AreaCode=‘1‘")
119 || a.AreaCode.SqlFunc("AreaCode=Parent"))
120 .ToList();
121 }
122 }
单表查询
1 /// <summary>
2 /// 多表查询
3 /// </summary>
4 public static void multilist_table()
5 {
6
7 using (var sql = new SqlModel<T_ST_Role, T_ST_Role_Permission>())
8 {
9 int count;
10 var left = sql.SqlSelect((a, b) => new { NameTest = a.RoleName, b.PermissionCode })
11 .SqlJionLeft((a, b) => b)
12 .SqlOn((a, b) => a.RoleGuid == b.RoleGuid)
13 .SqlOrderBy((a, b) => b.PermissionCode)
14 .SqlWhere((a, b) => a.RoleCode == "1")
15 .ToList();
16 count = left.Count;
17
18 var right = sql.SqlSelect((a, b) => new { NameTest = a.RoleName, b.PermissionCode })
19 .SqlJionRight((a, b) => b)
20 .SqlOn((a, b) => a.RoleGuid == b.RoleGuid)
21 .ToList();
22
23 var full = sql.SqlSelect((a, b) => new { NameTest = a.RoleName, b.PermissionCode, })
24 .SqlJionFull((a, b) => b)
25 .SqlOn((a, b) => a.RoleGuid == b.RoleGuid)
26 .ToList();
27
28 var inner = sql.SqlSelect((a, b) => new { NameTest = a.RoleName, b.PermissionCode })
29 .SqlJionInner((a, b) => b)
30 .SqlOn((a, b) => a.RoleGuid == b.RoleGuid)
31 .ToList();
32
33 var page = sql.SqlPage((a, b) => new { a.RoleGuid, NameTest = a.RoleName, b.PermissionCode }, 1, 20)
34 .SqlJionLeft((a, b) => b).SqlOn((a, b) => a.RoleGuid == b.RoleGuid)
35 .SqlWhere((a, b) => a.RoleCode == "R000001")
36 .SqlOrderBy((a, b) => b.PermissionCode)//.SqlOrderBy(o => new { o.PermissionCode })
37 .ToPageList();
38
39 }
40
41 using (var sql = new SqlModel<T_ST_Role, T_ST_Role_Permission, T_ST_Permission, T_ST_User_Role>())
42 {
43 var data = sql.SqlSelect((a, b, c, d) => new { a.RoleGuid, a.RoleName, b.Role_PermissionGuid, c.PermissionCode })
44 .SqlJionLeft((a, b, c, d) => b).SqlOn((a, b, c, d) => a.RoleGuid == b.RoleGuid)
45 .SqlJionRight((a, b, c, d) => c).SqlOn((a, b, c, d) => b.PermissionGuid == c.PermissionGuid)
46 .SqlJionLeft((a, b, c, d) => d).SqlOn((a, b, c, d) => a.RoleGuid == d.RoleGuid)
47 .ToList();
48
49 var page = sql.SqlPage((a, b, c, d) => new { a.RoleGuid, a.RoleName, b.Role_PermissionGuid, c.PermissionCode })
50 .SqlJionLeft((a, b, c, d) => b).SqlOn((a, b, c, d) => a.RoleGuid == b.RoleGuid)
51 .SqlJionRight((a, b, c, d) => c).SqlOn((a, b, c, d) => b.PermissionGuid == c.PermissionGuid)
52 .SqlJionLeft((a, b, c, d) => d).SqlOn((a, b, c, d) => a.RoleGuid == d.RoleGuid)
53 .ToPageList();
54 }
55 }
多表查询
1 /// <summary>
2 /// groupby case when then
3 /// </summary>
4 public static void groupby_casewhenthe()
5 {
6 using (var sql = new SqlModel<Students>())
7 {
8 //case when then查询方式1
9 //CASE WHEN age=16 THEN ‘16岁‘ WHEN age=18 THEN ‘18岁‘ WHEN age=20 THEN ‘20岁‘else ‘可选‘ END AS remark
10 var casewh = sql
11 .SqlNewSelect(a =>
12 new
13 {
14 a.Name,
15 Remark = a.CaseWhen(b => b.Age == 16).Then("16岁").When(b => b.Age == 18).Then("18岁").When(b => b.Age == 20).Then("20岁").Else("其它").End()
16 }).First();
17 //case when then查询方式2 多条件选择
18 //CASE Age WHEN 16 THEN ‘16岁‘ WHEN 18 THEN ‘18岁‘ WHEN 20 THEN ‘20岁‘else ‘可选‘ END AS remark
19 var casewh2 = sql
20 .SqlNewSelect(a =>
21 new
22 {
23 a.Name,
24 Remark = a.Case(a.Age).When(16).Then("16岁").When(18).Then("18岁").When(20).Then("20岁").Else("其它").End()
25 }).First();
26 //group by查询
27 var fun = sql
28 .SqlNewSelect(a => new
29 {
30 a.Name,
31 asName = a.Name.SqlCount(),
32 asAge = a.Age.SqlSum(),
33 asMaxAge = a.Age.SqlMax(),
34 asMinAge = a.Age.SqlMin(),
35 asAvg = a.Age.SqlAVG()
36 })
37 .SqlWhere(a => a.Age == 14)
38 .SqlGroupBy(a => new { a.Name, a.Age })
39 .SqlHaving(a => a.Name == "name_1500081")
40 .SqlOrderBy(a => a.Name).First();
41
42 Console.WriteLine(fun.asMaxAge + casewh.Name);
43 }
44 }
Group查询,Case查询
时间： 2024-12-21 19:56:28