sql的行转列(PIVOT)与列转行(UNPIVOT) webapi 跨域问题 Dapper 链式查询 扩展 T4 代码生成 Demo (抽奖程序)
sql的行转列(PIVOT)与列转行(UNPIVOT)
在做数据统计的时候,行转列,列转行是经常碰到的问题。case when方式太麻烦了,而且可扩展性不强,可以使用 PIVOT,UNPIVOT比较快速实现行转列,列转行,而且可扩展性强
一、行转列
1、测试数据准备

CREATE TABLE [StudentScores] ( [UserName] NVARCHAR(20), --学生姓名 [Subject] NVARCHAR(30), --科目 [Score] FLOAT, --成绩 ) INSERT INTO [StudentScores] SELECT '张三', '语文', 80 INSERT INTO [StudentScores] SELECT '张三', '数学', 90 INSERT INTO [StudentScores] SELECT '张三', '英语', 70 INSERT INTO [StudentScores] SELECT '张三', '生物', 85 INSERT INTO [StudentScores] SELECT '李四', '语文', 80 INSERT INTO [StudentScores] SELECT '李四', '数学', 92 INSERT INTO [StudentScores] SELECT '李四', '英语', 76 INSERT INTO [StudentScores] SELECT '李四', '生物', 88 INSERT INTO [StudentScores] SELECT '码农', '语文', 60 INSERT INTO [StudentScores] SELECT '码农', '数学', 82 INSERT INTO [StudentScores] SELECT '码农', '英语', 96 INSERT INTO [StudentScores] SELECT '码农', '生物', 78


2、行转列sql

SELECT * FROM [StudentScores] /*数据源*/
AS P
PIVOT
(
SUM(Score/*行转列后 列的值*/) FOR
p.Subject/*需要行转列的列*/ IN ([语文],[数学],[英语],[生物]/*列的值*/)
) AS T

执行结果:

二、列转行
1、测试数据准备

CREATE TABLE ProgrectDetail
(
ProgrectName NVARCHAR(20), --工程名称
OverseaSupply INT, --海外供应商供给数量
NativeSupply INT, --国内供应商供给数量
SouthSupply INT, --南方供应商供给数量
NorthSupply INT --北方供应商供给数量
)
INSERT INTO ProgrectDetail
SELECT 'A', 100, 200, 50, 50
UNION ALL
SELECT 'B', 200, 300, 150, 150
UNION ALL
SELECT 'C', 159, 400, 20, 320
UNION ALL


2、列转行的sql

SELECT P.ProgrectName,P.Supplier,P.SupplyNum
FROM
(
SELECT ProgrectName, OverseaSupply, NativeSupply,
SouthSupply, NorthSupply
FROM ProgrectDetail
)T
UNPIVOT
(
SupplyNum FOR Supplier IN
(OverseaSupply, NativeSupply, SouthSupply, NorthSupply )
) P

执行结果:

webapi 跨域问题
参考:http://www.cnblogs.com/chenxizhang/p/3821703.html
给自己做个笔记
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Credentials", "true");
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Headers", "origin,x-requested-with,content-type");
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Methods", "POST,GET,OPTIONS");
HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "*");
在web.config中添加这段代码

<system.webServer> <httpProtocol> <customHeaders> <add name="Access-Control-Allow-Origin" value="*" /> <add name="Access-Control-Allow-Headers" value="Content-Type" /> <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" /> </customHeaders> </httpProtocol> <handlers> <remove name="ExtensionlessUrlHandler-Integrated-4.0" /> <remove name="OPTIONSVerbHandler" /> <remove name="TRACEVerbHandler" /> <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" /> </handlers> </system.webServer>

Dapper 链式查询 扩展
Dapper 链式查询扩展 DapperSqlMaker
Github地址:https://github.com/mumumutou/DapperSqlMaker 欢迎大佬加入
Demo:
- 查询 TestsDapperSqlMaker\DapperSqlMaker.Test\ SelectDapperSqlMakerTest.cs
- 添加 TestsDapperSqlMaker\DapperSqlMaker.Test\ InsertDapperSqlMakerTest.cs
- 更新 TestsDapperSqlMaker\DapperSqlMaker.Test\ UpdateDapperSqlMakerTest.cs
- 删除 TestsDapperSqlMaker\DapperSqlMaker.Test\ DeleteDapperSqlMakerTest.cs
- 上下文类 TestsDapperSqlMaker\DbDapperSqlMaker\ LockDapperUtilsqlite.cs
简单栗子:
1.查询-联表查询,分页

1 public void 三表联表分页测试()
2 {
3 var arruser = new int[2] { 1,2 }; //
4 string uall = "b.*", pn1 = "%蛋蛋%", pn2 = "%m%";
5 LockPers lpmodel = new LockPers() { IsDel = false};
6 Users umodel = new Users() { UserName = "jiaojiao" };
7 SynNote snmodel = new SynNote() { Name = "木头" };
8 Expression<Func<LockPers, Users, SynNote, bool>> where = PredicateBuilder.WhereStart<LockPers, Users, SynNote>();
9 where = where.And((l, u, s) => ( l.Name.Contains(pn1) || l.Name.Contains(pn2) ));
10 where = where.And((lpw, uw, sn) => lpw.IsDel == lpmodel.IsDel);
11 where = where.And((l, u, s) => u.UserName == umodel.UserName);
12 where = where.And((l, u, s) => s.Name == snmodel.Name );
13 where = where.And((l, u, s) => SM.In(u.Id, arruser));
14
15 DapperSqlMaker<LockPers, Users, SynNote> query = LockDapperUtilsqlite<LockPers, Users, SynNote>
16 .Selec()
17 .Column((lp, u, s) => //null) //查询所有字段
18 new { lp.Name, lpid = lp.Id, x = "LENGTH(a.Prompt) as len", b = SM.Sql(uall) , scontent = s.Content, sname = s.Name })
19 .FromJoin(JoinType.Left, (lpp, uu, snn) => uu.Id == lpp.UserId
20 , JoinType.Inner, (lpp, uu, snn) => uu.Id == snn.UserId)
21 .Where(where)
22 .Order((lp, w, sn) => new { lp.EditCount, x = SM.OrderDesc(lp.Name), sn.Content });
23
24 var result = query.ExcuteSelect();
25 WriteJson(result); // 查询结果
26
27 Tuple<StringBuilder, DynamicParameters> resultsqlparams = query.RawSqlParams();
28 WriteSqlParams(resultsqlparams); // 打印sql和参数
29
30 int page = 2, rows = 3, records;
31 var result2 = query.LoadPagelt(page, rows, out records);
32 WriteJson(result2); // 查询结果
33 }

生成的sql :

select a.Name as Name, a.Id as lpid
, LENGTH(a.Prompt) as len, b.*
, c.Content as scontent, c.Name as sname
from LockPers a
left join Users b on b.Id = a.UserId
inner join SynNote c on b.Id = c.UserId
where ( a.Name like @Name0 or a.Name like @Name1 )
and a.IsDel = @IsDel2 and b.UserName = @UserName3
and c.Name = @Name4 and b.Id in @Id
order by a.EditCount, a.Name desc , c.Content

2.更新-更新部分字段

1 [Test]
2 public void 更新部分字段测试lt()
3 {
4 var issucs = LockDapperUtilsqlite<LockPers>.Cud.Update(
5 s =>
6 {
7 s.Name = "测试bool修改1";
8 s.Content = "update方法内赋值修改字段";
9 s.IsDel = true;
10 },
11 w => w.Name == "测试bool修改1" && w.IsDel == true
12 );
13 Console.WriteLine(issucs);
14 }

3.七联表以上待扩展 copy六联表修改3个文件
- DapperSqlMaker
- Template_DapperSqlMaker 上下文类
- PredicateBuilder 条件拼接类
4.实体生成T4模板使用方法 https://www.cnblogs.com/cl-blogs/p/7205954.html
T4 代码生成 Demo (抽奖程序)
参考自这位大狮的: https://github.com/Pencroff/Dapper-DAL/blob/master/Dapper-DAL/Models/ModelGenerator.tt
项目Demo下载 http://download.csdn.net/detail/qq_21533697/9904071
- 支持Oracle,MSSQL,SQLite
- Demo项目是个抽奖小程序,抽奖只用到了LuckDraw表
- Demo用的SQLite包含库方便直接运行
- 里面用到Dapper就只写了Model层的模板,
文件目录

T4库
表结构读取抽象类 SchemaReader.ttinclude

1 <#+
2 /*
3 The contents of this file are subject to the New BSD
4 License (the "License"); you may not use this file
5 except in compliance with the License. You may obtain a copy of
6 the License at http://www.opensource.org/licenses/bsd-license.php
7
8 Software distributed under the License is distributed on an
9 "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
10 implied. See the License for the specific language governing
11 rights and limitations under the License.
12 */
13
14 string ConnectionString = "";
15 string TableFilter = "";
16 string TopNamespace = "";
17 string Namespace = "";
18 string ClassPrefix = "";
19 string ClassSuffix = "";
20 string SchemaName = null;
21 bool IncludeViews;
22 string[] ExcludeTablePrefixes = new string[]{};
23 string _connectionString="";
24 string _providerName="";
25
26 static Regex rxCleanUp = new Regex(@"[^\w\d_]", RegexOptions.Compiled);
27
28 static Func<string, string> CleanUp = (str) =>
29 {
30 str = rxCleanUp.Replace(str, "_");
31 if (char.IsDigit(str[0])) str = "_" + str;
32
33 return str;
34 };
35
36 string CheckNullable(Column col)
37 {
38 string result="";
39 if(col.IsNullable &&
40 col.PropertyType !="byte[]" &&
41 col.PropertyType !="string" &&
42 col.PropertyType !="Microsoft.SqlServer.Types.SqlGeography" &&
43 col.PropertyType !="Microsoft.SqlServer.Types.SqlGeometry"
44 )
45 result="?";
46 return result;
47 }
48
49 static bool IsExcluded(string tablename, string[] ExcludeTablePrefixes)
50 {
51 for (int i = 0; i < ExcludeTablePrefixes.Length; i++)
52 {
53 string s = ExcludeTablePrefixes[i];
54 if(tablename.StartsWith(s)) return true;
55 }
56 return false;
57 }
58
59
60 abstract class SchemaReader
61 {
62 public abstract Tables ReadSchema(string connstr, string tableFilter);
63 public GeneratedTextTransformation outer;
64 public void WriteLine(string o)
65 {
66 outer.WriteLine(o);
67 }
68
69 public string GetPropertyType(string sqlType)
70 {
71 string sysType = "string";
72 switch (sqlType)
73 {
74 case "bigint":
75 sysType = "long";
76 break;
77 case "smallint":
78 sysType = "short";
79 break;
80 case "int":
81 case "number":
82 case "integer":
83 sysType = "int";
84 break;
85 case "uniqueidentifier":
86 sysType = "Guid";
87 break;
88 case "smalldatetime":
89 case "datetime":
90 case "date":
91 case "time":
92 sysType = "DateTime";
93 break;
94 case "float":
95 sysType = "double";
96 break;
97 case "real":
98 sysType = "float";
99 break;
100 case "numeric":
101 case "smallmoney":
102 case "decimal":
103 case "money":
104 sysType = "decimal";
105 break;
106 case "tinyint":
107 sysType = "byte";
108 break;
109 case "bit":
110 sysType = "bool";
111 break;
112 case "image":
113 case "binary":
114 case "varbinary":
115 case "timestamp":
116 sysType = "byte[]";
117 break;
118 case "geography":
119 sysType = "Microsoft.SqlServer.Types.SqlGeography";
120 break;
121 case "geometry":
122 sysType = "Microsoft.SqlServer.Types.SqlGeometry";
123 break;
124 }
125 return sysType;
126 }
127 }
128
129 public class Table
130 {
131 public List<Column> Columns;
132 public string Name;
133 public string Schema;
134 public bool IsView;
135 public string CleanName;
136 public string ClassName;
137 public string SequenceName;
138 public bool Ignore;
139
140 public Column PK
141 {
142 get
143 {
144 return this.Columns.SingleOrDefault(x=>x.IsPK);
145 }
146 }
147
148 public Column GetColumn(string columnName)
149 {
150 return Columns.Single(x=>string.Compare(x.Name, columnName, true)==0);
151 }
152
153 public Column this[string columnName]
154 {
155 get
156 {
157 return GetColumn(columnName);
158 }
159 }
160
161 }
162
163 public class Column
164 {
165 public string Name;
166 public string PropertyName;
167 public string PropertyType;
168 public string DbType;
169 public bool IsPK;
170 public bool IsNullable;
171 public bool IsAutoIncrement;
172 public bool Ignore;
173 }
174
175 public class Tables : List<Table>
176 {
177 public Tables()
178 {
179 }
180
181 public Table GetTable(string tableName)
182 {
183 return this.Single(x=>string.Compare(x.Name, tableName, true)==0);
184 }
185
186 public Table this[string tableName]
187 {
188 get
189 {
190 return GetTable(tableName);
191 }
192 }
193
194 }
195
196 #>

SQLite表结构读取实现 SQLiteSchemaReader.ttinclude

1 <#@ include file=".\SchemaReader.ttinclude" #>
2 <#+
3 Tables LoadTables()
4 {
5
6 WriteLine("// This file was automatically generated by the Dapper.SimpleCRUD T4 Template");
7 WriteLine("// Do not make changes directly to this file - edit the template instead");
8 WriteLine("// ");
9 WriteLine("// The following connection settings were used to generate this file");
10 WriteLine("// ");
11 WriteLine("// Connection String : `{0}`", ConnectionString);
12 WriteLine("");
13
14 //DbProviderFactory _factory ;
15 try
16 {
17 // _factory = DbProviderFactories.GetFactory(ProviderName);
18 }
19 catch (Exception x)
20 {
21 var error=x.Message.Replace("\r\n", "\n").Replace("\n", " ");
22 WriteLine("");
23 WriteLine("// -----------------------------------------------------------------------------------------");
24 WriteLine("// -----------------------------------------------------------------------------------------");
25 WriteLine("");
26 return new Tables();
27 }
28
29 try
30 {
31 Tables result;
32
33 SchemaReader reader= new SqliteSchemaReader();
34 result=reader.ReadSchema(ConnectionString, TableFilter);
35
36 for (int i=result.Count-1; i>=0; i--)
37 {
38 if (SchemaName!=null && string.Compare(result[i].Schema, SchemaName, true)!=0)
39 {
40 result.RemoveAt(i);
41 continue;
42 }
43 if (!IncludeViews && result[i].IsView)
44 {
45 result.RemoveAt(i);
46 continue;
47 }
48 }
49
50
51
52 var rxClean = new Regex("^(Equals|GetHashCode|GetType|ToString|repo|Save|IsNew|Insert|Update|Delete|Exists|SingleOrDefault|Single|First|FirstOrDefault|Fetch|Page|Query)$");
53 foreach (var t in result)
54 {
55 t.ClassName = ClassPrefix + t.ClassName + ClassSuffix;
56 foreach (var c in t.Columns)
57 {
58 c.PropertyName = rxClean.Replace(c.PropertyName, "_$1");
59
60 // Make sure property name doesn't clash with class name
61 if (c.PropertyName == t.ClassName)
62 c.PropertyName = "_" + c.PropertyName;
63 }
64 }
65
66 return result;
67 }
68 catch (Exception x)
69 {
70 var error=x.Message.Replace("\r\n", "\n").Replace("\n", " ");
71 Warning(string.Format("Failed to read database schema - {0}", error));
72 WriteLine("");
73 WriteLine("// -----------------------------------------------------------------------------------------");
74 WriteLine("// Failed to read database schema - {0}", error);
75 WriteLine("// -----------------------------------------------------------------------------------------");
76 WriteLine("");
77 return new Tables();
78 }
79
80
81 }
82
83 class SqliteSchemaReader : SchemaReader
84 {
85
86 private string _connstr {get;set;}
87
88 public override Tables ReadSchema(string connstr, string tableFilter)
89 {
90 _connstr = connstr;
91 var result = new Tables();
92 //pull the tables in a reader
93 using (IDataReader rdr = ExecuteReader(TABLE_SQL + tableFilter)) // SQLitehelper.
94 {
95 while (rdr.Read())
96 {
97 Table tbl = new Table();
98 tbl.Name = rdr["name"].ToString();
99 //tbl.Schema = rdr["TABLE_SCHEMA"].ToString();
100 //tbl.IsView = string.Compare(rdr["TABLE_TYPE"].ToString(), "View", true) == 0;
101 tbl.CleanName = CleanUp(tbl.Name);
102 // tbl.CleanName = T4Generator.CleanUp(tbl.Name);
103 if (tbl.CleanName.StartsWith("tbl_")) tbl.CleanName = tbl.CleanName.Replace("tbl_", "");
104 if (tbl.CleanName.StartsWith("tbl")) tbl.CleanName = tbl.CleanName.Replace("tbl", "");
105 tbl.CleanName = tbl.CleanName.Replace("_", "");
106 tbl.ClassName = tbl.CleanName;
107
108 result.Add(tbl);
109 }
110 }
111
112 foreach (var tbl in result)
113 {
114 tbl.Columns = LoadColumns(tbl);
115
116 //Mark the primary key
117 //string PrimaryKey = GetPK(tbl.Schema, tbl.Name);
118 //var pkColumn = tbl.Columns.SingleOrDefault(x => x.Name.ToLower().Trim() == PrimaryKey.ToLower().Trim());
119 //if (pkColumn != null)
120 //{
121 // pkColumn.IsPK = true;
122 //}
123 }
124
125
126 return result;
127 }
128
129 List<Column> LoadColumns(Table tbl)
130 {
131 var result = new List<Column>();
132 using (IDataReader rdr = ExecuteReader(COLUMN_SQL.Replace("@tableName", tbl.Name))) // SQLitehelper.
133 {
134 while (rdr.Read())
135 {
136 Column col = new Column();
137 col.Name = rdr["name"].ToString();
138 col.PropertyName = CleanUp(col.Name);
139 //col.PropertyName = T4Generator.CleanUp(col.Name);
140 col.PropertyType = base.GetPropertyType(rdr["type"].ToString().ToLower());
141 col.IsNullable = rdr["notnull"].ToString() != "1";
142 //col.IsAutoIncrement = false; //((int)rdr["IsIdentity"]) == 1;
143 col.IsPK = rdr["pk"].ToString() == "1";
144 result.Add(col);
145 }
146 }
147
148 return result;
149 }
150
151 string Table_Filter = " ";
152
153 const string TABLE_SQL = " select name from sqlite_master where type = 'table' ";
154
155 const string COLUMN_SQL = " PRAGMA table_info(@tableName) ";
156
157 /// <summary>
158 /// 查询
159 /// </summary>
160 /// <param name="sql">sql语句</param>
161 /// <param name="slPars">参数</param>
162 /// <returns>发挥SQLiteDataReader</returns>
163 public SQLiteDataReader ExecuteReader(string sql, params SQLiteParameter[] slPars)
164 {
165 SQLiteConnection conn = new SQLiteConnection(_connstr);
166 using (SQLiteCommand cmd = new SQLiteCommand(sql,conn))
167 {
168 if (slPars != null)
169 {
170 cmd.Parameters.AddRange(slPars);
171 }
172 try
173 {
174 conn.Open();
175 return cmd.ExecuteReader(CommandBehavior.CloseConnection);
176 }
177 catch(Exception ex)
178 {
179 conn.Close();
180 conn.Dispose();
181 throw ex;
182 }
183
184 }
185
186 }
187
188 }
189 #>

SQLite配置文件 SQLiteInit.ttinclude
1.配置连接串 注意修改连接串为自己对应的 ConnectionString = @"Data Source=E:/cc/test/LotterySite/Lib/db/cater.db;";
2.需要生成的表 3.顶级命名空间 4.一个库对应一个配置文件 (开始是把这些配置直接写在各层模板文件的,后来涉及多库的切换,每个文件改链接麻烦)

1 <#@ include file="./SQLiteSchemaReader.ttinclude" #>
2 <# // 初始化文件 一个库对应一个ttinclude文件
3 // Settings 初始化配置
4 ConnectionString = @"Data Source=E:/cc/test/LotterySite/Lib/db/cater.db;"; // 连接串
5 TableFilter = " and name in ('LuckDraw') "; // 过滤表
6 TopNamespace = "FW"; // 顶级命名空间
7 ClassPrefix = "";
8 ClassSuffix = "";
9 IncludeViews = true;
10 ExcludeTablePrefixes = new string[]{"aspnet_","webpages_"};
11
12 // Read schema
13 var tables = LoadTables(); //读取的所有表结构
14 #>

SQLite 模板使用

1 <#@ template hostspecific="True" #>
2 <#@ include file="EF.Utility.CS.ttinclude"#>
3 <#@ include file="$(SolutionDir)\FW.Common\T4Ttinclude\SQLiteInit.ttinclude" #>
4 <#@ assembly name="EnvDTE" #>
5 <#@ assembly name="System.Data" #>
6 <#@ assembly name="System.Data.Entity.Design" #>
7 <#@ assembly name="System.Xml" #>
8 <#@ assembly name="System.Configuration" #>
9 <#@ assembly name="$(SolutionDir)\Lib\sqlite\System.Data.SQLite.dll" #>
10
11 <#@ import namespace="System.Collections.Generic" #>
12 <#@ import namespace="System.Data" #>
13 <#@ import namespace="System.Data.Common" #>
14 <#@ import namespace="System.Diagnostics" #>
15 <#@ import namespace="System.Globalization" #>
16 <#@ import namespace="System.IO" #>
17 <#@ import namespace="System.Linq" #>
18 <#@ import namespace="System.Text" #>
19 <#@ import namespace="System.Text.RegularExpressions" #>
20 <#@ import namespace="System.Configuration" #>
21 <#@ import namespace="System.Data.SQLite" #>
22 <#@ output extension=".cst"#>
23
24
25 <#
26 Namespace = TopNamespace + ".TestModel";
27 // Read schema
28
29 EntityFrameworkTemplateFileManager fileManager = EntityFrameworkTemplateFileManager.Create(this); // 多文件生成
30 /*
31 // Tweak Schema
32 tables["tablename"].Ignore = true; // To ignore a table
33 tables["tablename"].ClassName = "newname"; // To change the class name of a table
34 tables["tablename"]["columnname"].Ignore = true; // To ignore a column
35 tables["tablename"]["columnname"].PropertyName="newname"; // To change the property name of a column
36 tables["tablename"]["columnname"].PropertyType="bool"; // To change the property type of a column
37 */
38 #>
39
40 <# fileManager.StartHeader(); #>
41
42 using System;
43 using Dapper;
44 using Dapper.Contrib.Extensions;
45
46 namespace <#=Namespace #>
47 {
48
49 <# fileManager.EndBlock(); #>
50
51
52 <#
53 foreach(Table tbl in from t in tables where !t.Ignore select t){
54 if(IsExcluded(tbl.Name, ExcludeTablePrefixes)) continue;
55
56 fileManager.StartNewFile(tbl.Name+".cs"); // 新建文件
57 #>
58 /// <summary>
59 /// A class which represents the <#=tbl.Name#> <#=(tbl.IsView)?"view":"table"#>.
60 /// </summary>
61 [Table("[<#=tbl.Name#>]")]
62 public partial class <#=tbl.ClassName#>
63 {
64 /* <#foreach(Column col in from c in tbl.Columns where !c.Ignore select c) {#> <#=col.PropertyName #> <#}#> */
65
66 <#foreach(Column col in from c in tbl.Columns where !c.Ignore select c)
67 {#>
68 <# if (tbl.PK!=null && tbl.PK.Name==col.PropertyName) { #>
69 [Key]
70 <#}#>
71 public virtual <#=col.PropertyType #><#=CheckNullable(col)#> <#=col.PropertyName #> { get; set; }
72 <#}#>
73 }
74
75 <#}#>
76
77 <# fileManager.StartFooter(); #>
78 } // namespace
79 <# fileManager.EndBlock(); #>
80 <# fileManager.Process(true); #>
81

模板属性:
Namespace 命名空间
tables 表结构集合
表属性
Name 数据库中的表名
ClassName 实体类名称
IsView 是否是视图(没怎么用)
PK.Name 主键列名
列属性
PropertyName 属性名称
PropertyType 属性类型
CheckNullable(col) 可空类型判断
注意引入对应的SQLite的T4配置库
<#@ include file="$(SolutionDir)\FW.Common\T4Ttinclude\SQLiteInit.ttinclude" #>
$(SolutionDir) 解决方案目录
sql的行转列(PIVOT)与列转行(UNPIVOT) webapi 跨域问题 Dapper 链式查询 扩展 T4 代码生成 Demo (抽奖程序)的更多相关文章
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