- 优化 ISelect.GroupBy 查询，增加 .Value 实现聚合源字段查询，ToList(a => a.Sum(a.Value.Score))；

- 增加 Expression string.Concat；

FreeSql.Tests/MySql/Curd/MySqlSelectTest.cs

@@ -726,7 +726,59 @@ namespace FreeSql.Tests.MySql {
 				arg1 = a.Avg(a.Key.mod4),
 				ccc2 = a.Key.tt2 ?? "now()",
 				//ccc = Convert.ToDateTime("now()"), partby = Convert.ToDecimal("sum(num) over(PARTITION BY server_id,os,rid,chn order by id desc)")
+				ccc3 = a.Max(a.Value.Item3.Id)
 			});
+
+			var testpid1 = g.mysql.Insert<TestTypeInfo>().AppendData(new TestTypeInfo { Name = "Name" + DateTime.Now.ToString("yyyyMMddHHmmss") }).ExecuteIdentity();
+			g.mysql.Insert<TestInfo>().AppendData(new TestInfo { Title = "Title" + DateTime.Now.ToString("yyyyMMddHHmmss"), CreateTime = DateTime.Now, TypeGuid = (int)testpid1 }).ExecuteAffrows();
+
+			var aggsql1 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist1 = select
+				.GroupBy(a => a.Title)
+				.ToList(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToSql(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToList(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql3 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid),
+					sum3 = b.Sum(b.Value.Type.Parent.Id)
+				});
 		}
 		[Fact]
 		public void ToAggregate() {

FreeSql.Tests/MySql/MySqlExpression/OtherTest.cs

@@ -1,4 +1,5 @@
 using FreeSql.DataAnnotations;
+using MySql.Data.MySqlClient;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -16,6 +17,10 @@ namespace FreeSql.Tests.MySqlExpression {
 
 		[Fact]
 		public void Array() {
+			int[] nullarr = null;
+			Assert.Throws<MySqlException>(() => { select.Where(a => nullarr.Contains(a.testFieldInt)).ToList(); });
+			Assert.Throws<MySqlException>(() => { select.Where(a => new int[0].Contains(a.testFieldInt)).ToList(); });
+
 			//in not in
 			var sql111 = select.Where(a => new[] { 1, 2, 3 }.Contains(a.testFieldInt)).ToList();
 			var sql112 = select.Where(a => new[] { 1, 2, 3 }.Contains(a.testFieldInt) == false).ToList();

FreeSql.Tests/Oracle/Curd/OracleSelectTest.cs

@@ -622,7 +622,59 @@ namespace FreeSql.Tests.Oracle {
 				arg1 = a.Avg(a.Key.mod4),
 				ccc2 = a.Key.tt2 ?? "now()",
 				//ccc = Convert.ToDateTime("now()"), partby = Convert.ToDecimal("sum(num) over(PARTITION BY server_id,os,rid,chn order by id desc)")
+				ccc3 = a.Max(a.Value.Item3.Id)
 			});
+
+			var testpid1 = g.oracle.Insert<TestTypeInfo>().AppendData(new TestTypeInfo { Name = "Name" + DateTime.Now.ToString("yyyyMMddHHmmss") }).ExecuteIdentity();
+			g.oracle.Insert<TestInfo>().AppendData(new TestInfo { Title = "Title" + DateTime.Now.ToString("yyyyMMddHHmmss"), CreateTime = DateTime.Now, TypeGuid = (int)testpid1 }).ExecuteAffrows();
+
+			var aggsql1 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist1 = select
+				.GroupBy(a => a.Title)
+				.ToList(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToSql(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToList(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql3 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid),
+					sum3 = b.Sum(b.Value.Type.Parent.Id)
+				});
 		}
 		[Fact]
 		public void ToAggregate() {

FreeSql.Tests/PostgreSQL/Curd/PostgreSQLSelectTest.cs

@@ -693,7 +693,54 @@ namespace FreeSql.Tests.PostgreSQL {
 				arg1 = a.Avg(a.Key.mod4),
 				ccc2 = a.Key.tt2 ?? "now()",
 				//ccc = Convert.ToDateTime("now()"), partby = Convert.ToDecimal("sum(num) over(PARTITION BY server_id,os,rid,chn order by id desc)")
+				ccc3 = a.Max(a.Value.Item3.Id)
 			});
+
+			var testpid1 = g.pgsql.Insert<TestTypeInfo>().AppendData(new TestTypeInfo { Name = "Name" + DateTime.Now.ToString("yyyyMMddHHmmss") }).ExecuteIdentity();
+			g.pgsql.Insert<TestInfo>().AppendData(new TestInfo { Title = "Title" + DateTime.Now.ToString("yyyyMMddHHmmss"), CreateTime = DateTime.Now, TypeGuid = (int)testpid1 }).ExecuteAffrows();
+
+			var aggsql1 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist1 = select
+				.GroupBy(a => a.Title)
+				.ToList(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToSql(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToList(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql3 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid),
+					sum3 = b.Sum(b.Value.Type.Parent.Id)
+				});
 		}
 		[Fact]
 		public void ToAggregate() {

FreeSql.Tests/SqlServer/Curd/SqlServerSelectTest.cs

@@ -624,7 +624,54 @@ namespace FreeSql.Tests.SqlServer {
 				arg1 = a.Avg(a.Key.mod4),
 				ccc2 = a.Key.tt2 ?? "now()",
 				//ccc = Convert.ToDateTime("now()"), partby = Convert.ToDecimal("sum(num) over(PARTITION BY server_id,os,rid,chn order by id desc)")
+				ccc3 = a.Max(a.Value.Item3.Id)
 			});
+
+			var testpid1 = _sqlserverFixture.SqlServer.Insert<TestTypeInfo>().AppendData(new TestTypeInfo { Name = "Name" + DateTime.Now.ToString("yyyyMMddHHmmss") }).ExecuteIdentity();
+			_sqlserverFixture.SqlServer.Insert<TestInfo>().AppendData(new TestInfo { Title = "Title" + DateTime.Now.ToString("yyyyMMddHHmmss"), CreateTime = DateTime.Now, TypeGuid = (int)testpid1 }).ExecuteAffrows();
+
+			var aggsql1 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist1 = select
+				.GroupBy(a => a.Title)
+				.ToList(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToSql(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToList(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql3 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum2 = b.Sum(b.Value.TypeGuid),
+					sum3 = b.Sum(b.Value.Type.Parent.Id)
+				});
 		}
 		[Fact]
 		public void ToAggregate() {

FreeSql.Tests/Sqlite/Curd/SqliteSelectTest.cs

@@ -568,7 +568,59 @@ namespace FreeSql.Tests.Sqlite {
 				arg1 = a.Avg(a.Key.mod4),
 				ccc2 = a.Key.tt2 ?? "now()",
 				//ccc = Convert.ToDateTime("now()"), partby = Convert.ToDecimal("sum(num) over(PARTITION BY server_id,os,rid,chn order by id desc)")
+				ccc3 = a.Max(a.Value.Item3.Id)
 			});
+
+			var testpid1 = g.sqlite.Insert<TestTypeInfo>().AppendData(new TestTypeInfo { Name = "Name" + DateTime.Now.ToString("yyyyMMddHHmmss") }).ExecuteIdentity();
+			g.sqlite.Insert<TestInfo>().AppendData(new TestInfo { Title = "Title" + DateTime.Now.ToString("yyyyMMddHHmmss"), CreateTime = DateTime.Now, TypeGuid = (int)testpid1 }).ExecuteAffrows();
+
+			var aggsql1 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist1 = select
+				.GroupBy(a => a.Title)
+				.ToList(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToSql(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToList(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql3 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid),
+					sum3 = b.Sum(b.Value.Type.Parent.Id)
+				});
 		}
 		[Fact]
 		public void ToAggregate() {

FreeSql.Tests/UnitTest1.cs

@@ -53,6 +53,56 @@ namespace FreeSql.Tests {
 
 		[Fact]
 		public void Test1() {
+			var testpid1 = g.mysql.Insert<TestTypeInfo>().AppendData(new TestTypeInfo { Name = "Name" + DateTime.Now.ToString("yyyyMMddHHmmss") }).ExecuteIdentity();
+			g.mysql.Insert<TestInfo>().AppendData(new TestInfo { Title = "Title" + DateTime.Now.ToString("yyyyMMddHHmmss"), CreateTime = DateTime.Now, TypeGuid = (int)testpid1 }).ExecuteAffrows();
+
+			var aggsql1 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist1 = select
+				.GroupBy(a => a.Title)
+				.ToList(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToSql(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+			var aggtolist2 = select
+				.GroupBy(a => new { a.Title, yyyy = string.Concat(a.CreateTime.Year, '-', a.CreateTime.Month) })
+				.ToList(b => new {
+					b.Key.Title,
+					b.Key.yyyy,
+
+					cou = b.Count(),
+					sum = b.Sum(b.Key.yyyy),
+					sum2 = b.Sum(b.Value.TypeGuid)
+				});
+
+			var aggsql3 = select
+				.GroupBy(a => a.Title)
+				.ToSql(b => new {
+					b.Key,
+					cou = b.Count(),
+					sum = b.Sum(b.Key),
+					sum2 = b.Sum(b.Value.TypeGuid),
+					sum3 = b.Sum(b.Value.Type.Parent.Parent.Id)
+				});
 
 			var sqlrepos = g.sqlite.GetRepository<TestTypeParentInfo, int>();
 			sqlrepos.Insert(new TestTypeParentInfo {
@@ -201,7 +251,9 @@ namespace FreeSql.Tests {
 			.Having(a => a.Count() > 0 && a.Avg(a.Key.mod4) > 0 && a.Max(a.Key.mod4) > 0)
 			.Having(a => a.Count() < 300 || a.Avg(a.Key.mod4) < 100)
 			.OrderBy(a => a.Key.tt2)
-			.OrderByDescending(a => a.Count()).ToSql(a => new { a.Key.mod4, a.Key.tt2, max = a.Max("a.id"), max2 = Convert.ToInt64("max(a.id)") });
+			.OrderByDescending(a => a.Count()).ToSql(a => new {
+				cou = a.Sum(a.Value.Item1.Id),
+				a.Key.mod4, a.Key.tt2, max = a.Max("a.id"), max2 = Convert.ToInt64("max(a.id)") });
 
 			var groupbysql2 = g.mysql.Select<TestInfo>().From<TestTypeInfo, TestTypeParentInfo>((s, b, c) => s
 				.Where(a => a.Id == 1)

FreeSql/FreeSql.csproj

@@ -2,7 +2,7 @@
 
 	<PropertyGroup>
 		<TargetFramework>netstandard2.0</TargetFramework>
-		<Version>0.5.4</Version>
+		<Version>0.5.4.1</Version>
 		<GeneratePackageOnBuild>true</GeneratePackageOnBuild>
 		<Authors>YeXiangQin</Authors>
 		<Description>FreeSql is the most convenient ORM in dotnet. It supports Mysql, Postgresql, SqlServer, Oracle and Sqlite.</Description>

FreeSql/Interface/Curd/ISelect/ISelect1.cs

@@ -271,7 +271,7 @@ namespace FreeSql {
 		/// </summary>
 		/// <param name="key"></param>
 		/// <returns></returns>
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, TKey>> exp);
+		ISelectGrouping<TKey, T1> GroupBy<TKey>(Expression<Func<T1, TKey>> exp);
 
 		/// <summary>
 		/// 按列排序，OrderBy(a => a.Time)

FreeSql/Interface/Curd/ISelect/ISelect10.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> Where(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, bool>> exp);
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TMember>> column);
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect2.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2> Where(Expression<Func<T1, T2, bool>> exp);
 		ISelect<T1, T2> WhereIf(bool condition, Expression<Func<T1, T2, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2)> GroupBy<TKey>(Expression<Func<T1, T2, TKey>> exp);
 
 		ISelect<T1, T2> OrderBy<TMember>(Expression<Func<T1, T2, TMember>> column);
 		ISelect<T1, T2> OrderByDescending<TMember>(Expression<Func<T1, T2, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect3.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3> Where(Expression<Func<T1, T2, T3, bool>> exp);
 		ISelect<T1, T2, T3> WhereIf(bool condition, Expression<Func<T1, T2, T3, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3)> GroupBy<TKey>(Expression<Func<T1, T2, T3, TKey>> exp);
 
 		ISelect<T1, T2, T3> OrderBy<TMember>(Expression<Func<T1, T2, T3, TMember>> column);
 		ISelect<T1, T2, T3> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect4.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4> Where(Expression<Func<T1, T2, T3, T4, bool>> exp);
 		ISelect<T1, T2, T3, T4> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, TMember>> column);
 		ISelect<T1, T2, T3, T4> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect5.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4, T5> Where(Expression<Func<T1, T2, T3, T4, T5, bool>> exp);
 		ISelect<T1, T2, T3, T4, T5> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, T5, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4, T5> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, T5, TMember>> column);
 		ISelect<T1, T2, T3, T4, T5> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, T5, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect6.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4, T5, T6> Where(Expression<Func<T1, T2, T3, T4, T5, T6, bool>> exp);
 		ISelect<T1, T2, T3, T4, T5, T6> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, T5, T6, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4, T5, T6> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, TMember>> column);
 		ISelect<T1, T2, T3, T4, T5, T6> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect7.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4, T5, T6, T7> Where(Expression<Func<T1, T2, T3, T4, T5, T6, T7, bool>> exp);
 		ISelect<T1, T2, T3, T4, T5, T6, T7> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, T5, T6, T7, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4, T5, T6, T7> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TMember>> column);
 		ISelect<T1, T2, T3, T4, T5, T6, T7> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect8.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8> Where(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, bool>> exp);
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7, T8)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TMember>> column);
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelect9.cs

@@ -32,7 +32,7 @@ namespace FreeSql {
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9> Where(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, bool>> exp);
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9> WhereIf(bool condition, Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, bool>> exp);
 
-		ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TKey>> exp);
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9)> GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TKey>> exp);
 
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9> OrderBy<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TMember>> column);
 		ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9> OrderByDescending<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TMember>> column);

FreeSql/Interface/Curd/ISelect/ISelectGrouping.cs

@@ -5,13 +5,13 @@ using System.Text;
 using System.Threading.Tasks;
 
 namespace FreeSql {
-	public interface ISelectGrouping<T1> {
+	public interface ISelectGrouping<TKey, TValue> {
 		/// <summary>
 		/// 按聚合条件过滤，Where(a => a.Count() > 10)
 		/// </summary>
 		/// <param name="exp">lambda表达式</param>
 		/// <returns></returns>
-		ISelectGrouping<T1> Having(Expression<Func<ISelectGroupingAggregate<T1>, bool>> exp);
+		ISelectGrouping<TKey, TValue> Having(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, bool>> exp);
 
 		/// <summary>
 		/// 按列排序，OrderBy(a => a.Time)
@@ -19,13 +19,13 @@ namespace FreeSql {
 		/// <typeparam name="TMember"></typeparam>
 		/// <param name="column"></param>
 		/// <returns></returns>
-		ISelectGrouping<T1> OrderBy<TMember>(Expression<Func<ISelectGroupingAggregate<T1>, TMember>> column);
+		ISelectGrouping<TKey, TValue> OrderBy<TMember>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TMember>> column);
 		/// <summary>
 		/// 按列倒向排序，OrderByDescending(a => a.Time)
 		/// </summary>
 		/// <param name="column">列</param>
 		/// <returns></returns>
-		ISelectGrouping<T1> OrderByDescending<TMember>(Expression<Func<ISelectGroupingAggregate<T1>, TMember>> column);
+		ISelectGrouping<TKey, TValue> OrderByDescending<TMember>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TMember>> column);
 
 		/// <summary>
 		/// 执行SQL查询，返回指定字段的记录，记录不存在时返回 Count 为 0 的列表
@@ -33,8 +33,8 @@ namespace FreeSql {
 		/// <typeparam name="TReturn">返回类型</typeparam>
 		/// <param name="select">选择列</param>
 		/// <returns></returns>
-		List<TReturn> ToList<TReturn>(Expression<Func<ISelectGroupingAggregate<T1>, TReturn>> select);
+		List<TReturn> ToList<TReturn>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TReturn>> select);
-		Task<List<TReturn>> ToListAsync<TReturn>(Expression<Func<ISelectGroupingAggregate<T1>, TReturn>> select);
+		Task<List<TReturn>> ToListAsync<TReturn>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TReturn>> select);
 
 		/// <summary>
 		/// 返回即将执行的SQL语句
@@ -42,7 +42,7 @@ namespace FreeSql {
 		/// <typeparam name="TReturn">返回类型</typeparam>
 		/// <param name="select">选择列</param>
 		/// <returns></returns>
-		string ToSql<TReturn>(Expression<Func<ISelectGroupingAggregate<T1>, TReturn>> select);
+		string ToSql<TReturn>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TReturn>> select);
 
 
 		/// <summary>
@@ -50,25 +50,25 @@ namespace FreeSql {
 		/// </summary>
 		/// <param name="offset"></param>
 		/// <returns></returns>
-		ISelectGrouping<T1> Skip(int offset);
+		ISelectGrouping<TKey, TValue> Skip(int offset);
 		/// <summary>
 		/// 查询向后偏移行数
 		/// </summary>
 		/// <param name="offset">行数</param>
 		/// <returns></returns>
-		ISelectGrouping<T1> Offset(int offset);
+		ISelectGrouping<TKey, TValue> Offset(int offset);
 		/// <summary>
 		/// 查询多少条数据
 		/// </summary>
 		/// <param name="limit"></param>
 		/// <returns></returns>
-		ISelectGrouping<T1> Limit(int limit);
+		ISelectGrouping<TKey, TValue> Limit(int limit);
 		/// <summary>
 		/// 查询多少条数据
 		/// </summary>
 		/// <param name="limit"></param>
 		/// <returns></returns>
-		ISelectGrouping<T1> Take(int limit);
+		ISelectGrouping<TKey, TValue> Take(int limit);
 
 		/// <summary>
 		/// 分页
@@ -76,14 +76,14 @@ namespace FreeSql {
 		/// <param name="pageIndex">第几页</param>
 		/// <param name="pageSize">每页多少</param>
 		/// <returns></returns>
-		ISelectGrouping<T1> Page(int pageIndex, int pageSize);
+		ISelectGrouping<TKey, TValue> Page(int pageIndex, int pageSize);
 	}
 
-	public interface ISelectGroupingAggregate<T1> {
+	public interface ISelectGroupingAggregate<TKey> {
 		/// <summary>
 		/// 分组的数据
 		/// </summary>
-		T1 Key { get; set; }
+		TKey Key { get; set; }
 		/// <summary>
 		/// 记录总数
 		/// </summary>
@@ -117,4 +117,10 @@ namespace FreeSql {
 		/// <returns></returns>
 		T3 Min<T3>(T3 column);
 	}
+	public interface ISelectGroupingAggregate<TKey, TValue> : ISelectGroupingAggregate<TKey> {
+		/// <summary>
+		/// 所有元素
+		/// </summary>
+		TValue Value { get; set; }
+	}
 }

FreeSql/Internal/CommonExpression.cs

@@ -726,7 +726,7 @@ namespace FreeSql.Internal {
 							case ExpressionType.MemberAccess:
 								
 								var exp2Type = exp2.Type;
-								if (exp2Type.FullName.StartsWith("FreeSql.ISelectGroupingAggregate`")) exp2Type = exp2Type.GenericTypeArguments.FirstOrDefault() ?? exp2.Type;
+								if (exp2Type.FullName.StartsWith("FreeSql.ISelectGroupingAggregate`")) exp2Type = exp2Type.GenericTypeArguments.LastOrDefault() ?? exp2.Type;
 								var tb2tmp = _common.GetTableByEntity(exp2Type);
 								var mp2 = exp2 as MemberExpression;
 								if (mp2?.Member.Name == "Key" && mp2.Expression.Type.FullName.StartsWith("FreeSql.ISelectGroupingAggregate`")) continue;
@@ -794,7 +794,7 @@ namespace FreeSql.Internal {
 				left = tmp;
 			}
 			if (right == "NULL") tryoper = tryoper == "=" ? " IS " : " IS NOT ";
-			if (tryoper == "+" && (expBinary.Left.Type.FullName == "System.String" || expBinary.Right.Type.FullName == "System.String")) return _common.StringConcat(left, right, expBinary.Left.Type, expBinary.Right.Type);
+			if (tryoper == "+" && (expBinary.Left.Type.FullName == "System.String" || expBinary.Right.Type.FullName == "System.String")) return _common.StringConcat(new[] { left, right }, new[] { expBinary.Left.Type, expBinary.Right.Type });
 			if (tryoper == "%") return _common.Mod(left, right, expBinary.Left.Type, expBinary.Right.Type);
 			if (_common._orm.Ado.DataType == DataType.MySql) {
 				//处理c#变态enum convert， a.EnumType1 == Xxx.Xxx，被转成了 Convert(a.EnumType1, Int32) == 1

FreeSql/Internal/CommonProvider/SelectProvider/Select0Provider.cs

@@ -679,14 +679,14 @@ namespace FreeSql.Internal.CommonProvider {
 		protected TMember InternalSum<TMember>(Expression exp) => this.ToList<TMember>($"sum({_commonExpression.ExpressionSelectColumn_MemberAccess(_tables, null, SelectTableInfoType.From, exp, true, null)})").FirstOrDefault();
 		async protected Task<TMember> InternalSumAsync<TMember>(Expression exp) => (await this.ToListAsync<TMember>($"sum({_commonExpression.ExpressionSelectColumn_MemberAccess(_tables, null, SelectTableInfoType.From, exp, true, null)})")).FirstOrDefault();
 
-		protected ISelectGrouping<TKey> InternalGroupBy<TKey>(Expression columns) {
+		protected ISelectGrouping<TKey, TValue> InternalGroupBy<TKey, TValue>(Expression columns) {
 			var map = new ReadAnonymousTypeInfo();
 			var field = new StringBuilder();
 			var index = -10000; //临时规则，不返回 as1
 
 			_commonExpression.ReadAnonymousField(_tables, field, map, ref index, columns, null);
 			this.GroupBy(field.Length > 0 ? field.Remove(0, 2).ToString() : null);
-			return new SelectGroupingProvider<TKey>(this, map, _commonExpression);
+			return new SelectGroupingProvider<TKey, TValue>(this, map, _commonExpression, _tables);
 		}
 		protected TSelect InternalJoin(Expression exp, SelectTableInfoType joinType) {
 			_commonExpression.ExpressionJoinLambda(_tables, joinType, exp, null);

FreeSql/Internal/CommonProvider/SelectProvider/Select10Provider.cs

@@ -44,10 +44,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)> ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)> (exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>.Max<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select1Provider.cs

@@ -87,10 +87,10 @@ namespace FreeSql.Internal.CommonProvider {
 
 		public abstract ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> From<T2, T3, T4, T5, T6, T7, T8, T9, T10>(Expression<Func<ISelectFromExpression<T1>, T2, T3, T4, T5, T6, T7, T8, T9, T10, ISelectFromExpression<T1>>> exp) where T2 : class where T3 : class where T4 : class where T5 : class where T6 : class where T7 : class where T8 : class where T9 : class where T10 : class;// { this.InternalFrom(exp?.Body); var ret = new Select10Provider<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>(_orm, _commonUtils, _commonExpression, null); Select0Provider<ISelect<T1>, T1>.CopyData(this, ret, exp?.Parameters); return ret; }
 
-		public ISelectGrouping<TKey> GroupBy<TKey>(Expression<Func<T1, TKey>> columns) {
+		public ISelectGrouping<TKey, T1> GroupBy<TKey>(Expression<Func<T1, TKey>> columns) {
-			if (columns == null) return this.InternalGroupBy<TKey>(columns);
+			if (columns == null) return this.InternalGroupBy<TKey, T1>(columns);
 			_tables[0].Parameter = columns.Parameters[0];
-			return this.InternalGroupBy<TKey>(columns);
+			return this.InternalGroupBy<TKey, T1>(columns);
 		}
 
 		public TMember Max<TMember>(Expression<Func<T1, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select2Provider.cs

@@ -28,10 +28,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2>.GroupBy<TKey>(Expression<Func<T1, T2, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2)> ISelect<T1, T2>.GroupBy<TKey>(Expression<Func<T1, T2, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2>.Max<TMember>(Expression<Func<T1, T2, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select3Provider.cs

@@ -30,10 +30,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3>.GroupBy<TKey>(Expression<Func<T1, T2, T3, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3)> ISelect<T1, T2, T3>.GroupBy<TKey>(Expression<Func<T1, T2, T3, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3>.Max<TMember>(Expression<Func<T1, T2, T3, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select4Provider.cs

@@ -32,10 +32,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4)> ISelect<T1, T2, T3, T4>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4>.Max<TMember>(Expression<Func<T1, T2, T3, T4, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select5Provider.cs

@@ -34,10 +34,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4, T5>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5)> ISelect<T1, T2, T3, T4, T5>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4, T5>.Max<TMember>(Expression<Func<T1, T2, T3, T4, T5, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select6Provider.cs

@@ -36,10 +36,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4, T5, T6>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6)> ISelect<T1, T2, T3, T4, T5, T6>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4, T5, T6>.Max<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select7Provider.cs

@@ -38,10 +38,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4, T5, T6, T7>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7)> ISelect<T1, T2, T3, T4, T5, T6, T7>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4, T5, T6, T7>.Max<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select8Provider.cs

@@ -40,10 +40,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4, T5, T6, T7, T8>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7, T8)> ISelect<T1, T2, T3, T4, T5, T6, T7, T8>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7, T8)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7, T8)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4, T5, T6, T7, T8>.Max<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/Select9Provider.cs

@@ -42,10 +42,10 @@ namespace FreeSql.Internal.CommonProvider {
 			return this.InternalAvgAsync<TMember>(column?.Body);
 		}
 
-		ISelectGrouping<TKey> ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TKey>> exp) {
+		ISelectGrouping<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9)> ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9>.GroupBy<TKey>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TKey>> exp) {
-			if (exp == null) return this.InternalGroupBy<TKey>(exp?.Body);
+			if (exp == null) return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9)>(exp?.Body);
 			for (var a = 0; a < exp.Parameters.Count; a++) _tables[a].Parameter = exp.Parameters[a];
-			return this.InternalGroupBy<TKey>(exp?.Body);
+			return this.InternalGroupBy<TKey, (T1, T2, T3, T4, T5, T6, T7, T8, T9)>(exp?.Body);
 		}
 
 		TMember ISelect<T1, T2, T3, T4, T5, T6, T7, T8, T9>.Max<TMember>(Expression<Func<T1, T2, T3, T4, T5, T6, T7, T8, T9, TMember>> column) {

FreeSql/Internal/CommonProvider/SelectProvider/SelectGroupingProvider.cs

@@ -8,48 +8,89 @@ using System.Text;
 using System.Threading.Tasks;
 
 namespace FreeSql.Internal.CommonProvider {
-	class SelectGroupingProvider<T1> : ISelectGrouping<T1> {
+	class SelectGroupingProvider<TKey, TValue> : ISelectGrouping<TKey, TValue> {
 
 		internal object _select;
 		internal ReadAnonymousTypeInfo _map;
 		internal CommonExpression _comonExp;
-		public SelectGroupingProvider(object select, ReadAnonymousTypeInfo map, CommonExpression comonExp) {
+		internal List<SelectTableInfo> _tables;
+		public SelectGroupingProvider(object select, ReadAnonymousTypeInfo map, CommonExpression comonExp, List<SelectTableInfo> tables) {
 			_select = select;
 			_map = map;
 			_comonExp = comonExp;
+			_tables = tables;
 		}
 
 		string getSelectGroupingMapString(Expression[] members) {
-			var read = _map;
+			if (members.Any() == false) return _map.DbField;
-			for (var a = 0; a < members.Length; a++) {
+			var parentName = ((members.FirstOrDefault() as MemberExpression)?.Expression as MemberExpression)?.Member.Name;
-				read = read.Childs.Where(z => z.CsName == (members[a] as MemberExpression)?.Member.Name).FirstOrDefault();
+			switch(parentName) {
-				if (read == null) return null;
+				case "Key":
+					var read = _map;
+					for (var a = 0; a < members.Length; a++) {
+						read = read.Childs.Where(z => z.CsName == (members[a] as MemberExpression)?.Member.Name).FirstOrDefault();
+						if (read == null) return null;
+					}
+					return read.DbField;
+				case "Value":
+					var tb = _tables.First();
+					var foridx = 0;
+					if (members.Length > 1) {
+						var mem0 = (members.FirstOrDefault() as MemberExpression);
+						var mem0Name = mem0?.Member.Name;
+						if (mem0Name?.StartsWith("Item") == true && int.TryParse(mem0Name.Substring(4), out var tryitemidx)) {
+							if (tryitemidx == 1) foridx++;
+							else {
+								var alias = $"SP10{(char)(96 + tryitemidx)}";
+								var tmptb = _tables.Where(a => a.AliasInit == alias && a.Table.Type == mem0.Type).FirstOrDefault();
+								if (tmptb != null) {
+									tb = tmptb;
+									foridx++;
+								}
+							}
+						}
+					}
+					var parmExp = Expression.Parameter(tb.Table.Type, tb.Alias);
+					Expression retExp = parmExp;
+					for (var a = foridx; a < members.Length; a++) {
+						switch(members[a].NodeType) {
+							case ExpressionType.Call:
+								retExp = Expression.Call(retExp, (members[a] as MethodCallExpression).Method);
+								break;
+							case ExpressionType.MemberAccess:
+								retExp = Expression.MakeMemberAccess(retExp, (members[a] as MemberExpression).Member);
+								break;
+							default:
+								return null;
+						}
+					}
+					return _comonExp.ExpressionLambdaToSql(retExp, _tables, null, null, SelectTableInfoType.From, true, true, CommonExpression.ExpressionStyle.Where);
 			}
-			return read.DbField;
+			return null;
 		}
 
-		public ISelectGrouping<T1> Having(Expression<Func<ISelectGroupingAggregate<T1>, bool>> exp) {
+		public ISelectGrouping<TKey, TValue> Having(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, bool>> exp) {
 			var sql = _comonExp.ExpressionWhereLambda(null, exp, getSelectGroupingMapString);
 			var method = _select.GetType().GetMethod("Having", new[] { typeof(string), typeof(object) });
 			method.Invoke(_select, new object[] { sql, null });
 			return this;
 		}
 
-		public ISelectGrouping<T1> OrderBy<TMember>(Expression<Func<ISelectGroupingAggregate<T1>, TMember>> column) {
+		public ISelectGrouping<TKey, TValue> OrderBy<TMember>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TMember>> column) {
 			var sql = _comonExp.ExpressionWhereLambda(null, column, getSelectGroupingMapString);
 			var method = _select.GetType().GetMethod("OrderBy", new[] { typeof(string), typeof(object) });
 			method.Invoke(_select, new object[] { sql, null });
 			return this;
 		}
 
-		public ISelectGrouping<T1> OrderByDescending<TMember>(Expression<Func<ISelectGroupingAggregate<T1>, TMember>> column) {
+		public ISelectGrouping<TKey, TValue> OrderByDescending<TMember>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TMember>> column) {
 			var sql = _comonExp.ExpressionWhereLambda(null, column, getSelectGroupingMapString);
 			var method = _select.GetType().GetMethod("OrderBy", new[] { typeof(string), typeof(object) });
 			method.Invoke(_select, new object[] { $"{sql} DESC", null });
 			return this;
 		}
 
-		public List<TReturn> ToList<TReturn>(Expression<Func<ISelectGroupingAggregate<T1>, TReturn>> select) {
+		public List<TReturn> ToList<TReturn>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TReturn>> select) {
 			var map = new ReadAnonymousTypeInfo();
 			var field = new StringBuilder();
 			var index = 0;
@@ -59,7 +100,7 @@ namespace FreeSql.Internal.CommonProvider {
 			method = method.MakeGenericMethod(typeof(TReturn));
 			return method.Invoke(_select, new object[] { (map, field.Length > 0 ? field.Remove(0, 2).ToString() : null) }) as List<TReturn>;
 		}
-		public Task<List<TReturn>> ToListAsync<TReturn>(Expression<Func<ISelectGroupingAggregate<T1>, TReturn>> select) {
+		public Task<List<TReturn>> ToListAsync<TReturn>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TReturn>> select) {
 			var map = new ReadAnonymousTypeInfo();
 			var field = new StringBuilder();
 			var index = 0;
@@ -70,7 +111,7 @@ namespace FreeSql.Internal.CommonProvider {
 			return method.Invoke(_select, new object[] { (map, field.Length > 0 ? field.Remove(0, 2).ToString() : null) }) as Task<List<TReturn>>;
 		}
 
-		public string ToSql<TReturn>(Expression<Func<ISelectGroupingAggregate<T1>, TReturn>> select) {
+		public string ToSql<TReturn>(Expression<Func<ISelectGroupingAggregate<TKey, TValue>, TReturn>> select) {
 			var map = new ReadAnonymousTypeInfo();
 			var field = new StringBuilder();
 			var index = 0;
@@ -80,21 +121,21 @@ namespace FreeSql.Internal.CommonProvider {
 			return method.Invoke(_select, new object[] { field.Length > 0 ? field.Remove(0, 2).ToString() : null }) as string;
 		}
 
-		public ISelectGrouping<T1> Skip(int offset) {
+		public ISelectGrouping<TKey, TValue> Skip(int offset) {
 			var method = _select.GetType().GetMethod("Skip", new[] { typeof(int) });
 			method.Invoke(_select, new object[] { offset });
 			return this;
 		}
-		public ISelectGrouping<T1> Offset(int offset) => this.Skip(offset);
+		public ISelectGrouping<TKey, TValue> Offset(int offset) => this.Skip(offset);
 
-		public ISelectGrouping<T1> Limit(int limit) {
+		public ISelectGrouping<TKey, TValue> Limit(int limit) {
 			var method = _select.GetType().GetMethod("Limit", new[] { typeof(int) });
 			method.Invoke(_select, new object[] { limit });
 			return this;
 		}
-		public ISelectGrouping<T1> Take(int limit) => this.Limit(limit);
+		public ISelectGrouping<TKey, TValue> Take(int limit) => this.Limit(limit);
 
-		public ISelectGrouping<T1> Page(int pageIndex, int pageSize) {
+		public ISelectGrouping<TKey, TValue> Page(int pageIndex, int pageSize) {
 			var method = _select.GetType().GetMethod("Page", new[] { typeof(int), typeof(int) });
 			method.Invoke(_select, new object[] { pageIndex, pageSize });
 			return this;

FreeSql/Internal/CommonUtils.cs

@@ -21,7 +21,7 @@ namespace FreeSql.Internal {
 		internal abstract string QuoteSqlName(string name);
 		internal abstract string QuoteParamterName(string name);
 		internal abstract string IsNull(string sql, object value);
-		internal abstract string StringConcat(string left, string right, Type leftType, Type rightType);
+		internal abstract string StringConcat(string[] objs, Type[] types);
 		internal abstract string Mod(string left, string right, Type leftType, Type rightType);
 		internal abstract string QuoteWriteParamter(Type type, string paramterName);
 		internal abstract string QuoteReadColumn(Type type, string columnName);

FreeSql/Internal/Model/SelectTableInfo.cs

@@ -3,7 +3,16 @@
 namespace FreeSql.Internal.Model {
 	class SelectTableInfo {
 		public TableInfo Table { get; set; }
-		public string Alias { get; set; }
+
+		private string _alias;
+		public string Alias {
+			get => _alias;
+			set {
+				_alias = value;
+				if (string.IsNullOrEmpty(AliasInit)) AliasInit = value;
+			}
+		}
+		public string AliasInit { get; set; }
 		public string On { get; set; }
 		public string NavigateCondition { get; set; }
 		public ParameterExpression Parameter { get; set; }

FreeSql/MySql/MySqlExpression.cs

@@ -208,6 +208,8 @@ namespace FreeSql.MySql {
 					case "IsNullOrEmpty":
 						var arg1 = getExp(exp.Arguments[0]);
 						return $"({arg1} is null or {arg1} = '')";
+					case "Concat":
+						return _common.StringConcat(exp.Arguments.Select(a => getExp(a)).ToArray(), null);
 				}
 			} else {
 				var left = getExp(exp.Object);
@@ -335,7 +337,7 @@ namespace FreeSql.MySql {
 						}
 						break;
 					case "Equals": return $"({left} = {getExp(exp.Arguments[0])})";
-					case "CompareTo": return $"timestampdiff(microsecond,{getExp(exp.Arguments[0])},{left})";
+					case "CompareTo": return $"timestampdiff(microsecond,{args1},{left})";
 					case "ToString": return $"date_format({left}, '%Y-%m-%d %H:%i:%s.%f')";
 				}
 			}

FreeSql/MySql/MySqlUtils.cs

@@ -4,6 +4,7 @@ using MySql.Data.MySqlClient;
 using System;
 using System.Collections.Generic;
 using System.Data.Common;
+using System.Linq;
 using System.Text;
 
 namespace FreeSql.MySql {
@@ -50,7 +51,7 @@ namespace FreeSql.MySql {
 		}
 		internal override string QuoteParamterName(string name) => $"?{(_orm.CodeFirst.IsSyncStructureToLower ? name.ToLower() : name)}";
 		internal override string IsNull(string sql, object value) => $"ifnull({sql}, {value})";
-		internal override string StringConcat(string left, string right, Type leftType, Type rightType) => $"concat({left}, {right})";
+		internal override string StringConcat(string[] objs, Type[] types) => $"concat({string.Join(", ", objs)})";
 		internal override string Mod(string left, string right, Type leftType, Type rightType) => $"{left} % {right}";
 		internal override string QuoteWriteParamter(Type type, string paramterName) {
 			switch (type.FullName) {

FreeSql/Oracle/OracleExpression.cs

@@ -208,6 +208,8 @@ namespace FreeSql.Oracle {
 					case "IsNullOrEmpty":
 						var arg1 = getExp(exp.Arguments[0]);
 						return $"({arg1} is null or {arg1} = '')";
+					case "Concat":
+						return _common.StringConcat(exp.Arguments.Select(a => getExp(a)).ToArray(), null);
 				}
 			} else {
 				var left = getExp(exp.Object);

FreeSql/Oracle/OracleUtils.cs

@@ -46,7 +46,7 @@ namespace FreeSql.Oracle {
 		}
 		internal override string QuoteParamterName(string name) => $":{(_orm.CodeFirst.IsSyncStructureToLower ? name.ToLower() : name)}";
 		internal override string IsNull(string sql, object value) => $"nvl({sql}, {value})";
-		internal override string StringConcat(string left, string right, Type leftType, Type rightType) => $"{left} || {right}";
+		internal override string StringConcat(string[] objs, Type[] types) => $"{string.Join(" || ", objs)}";
 		internal override string Mod(string left, string right, Type leftType, Type rightType) => $"mod({left}, {right})";
 
 		internal override string QuoteWriteParamter(Type type, string paramterName) => paramterName;

FreeSql/PostgreSQL/PostgreSQLExpression.cs

@@ -303,6 +303,8 @@ namespace FreeSql.PostgreSQL {
 					case "IsNullOrEmpty":
 						var arg1 = getExp(exp.Arguments[0]);
 						return $"({arg1} is null or {arg1} = '')";
+					case "Concat":
+						return _common.StringConcat(exp.Arguments.Select(a => getExp(a)).ToArray(), null);
 				}
 			} else {
 				var left = getExp(exp.Object);

FreeSql/PostgreSQL/PostgreSQLUtils.cs

@@ -105,7 +105,7 @@ namespace FreeSql.PostgreSQL {
 		}
 		internal override string QuoteParamterName(string name) => $"@{(_orm.CodeFirst.IsSyncStructureToLower ? name.ToLower() : name)}";
 		internal override string IsNull(string sql, object value) => $"coalesce({sql}, {value})";
-		internal override string StringConcat(string left, string right, Type leftType, Type rightType) => $"{left} || {right}";
+		internal override string StringConcat(string[] objs, Type[] types) => $"{string.Join(" || ", objs)}";
 		internal override string Mod(string left, string right, Type leftType, Type rightType) => $"{left} % {right}";
 
 		internal override string QuoteWriteParamter(Type type, string paramterName) => paramterName;

FreeSql/SqlServer/SqlServerExpression.cs

@@ -211,6 +211,8 @@ namespace FreeSql.SqlServer {
 					case "IsNullOrEmpty":
 						var arg1 = getExp(exp.Arguments[0]);
 						return $"({arg1} is null or {arg1} = '')";
+					case "Concat":
+						return _common.StringConcat(exp.Arguments.Select(a => getExp(a)).ToArray(), exp.Arguments.Select(a => a.Type).ToArray());
 				}
 			} else {
 				var left = getExp(exp.Object);

FreeSql/SqlServer/SqlServerUtils.cs

@@ -43,7 +43,13 @@ namespace FreeSql.SqlServer {
 		}
 		internal override string QuoteParamterName(string name) => $"@{(_orm.CodeFirst.IsSyncStructureToLower ? name.ToLower() : name)}";
 		internal override string IsNull(string sql, object value) => $"isnull({sql}, {value})";
-		internal override string StringConcat(string left, string right, Type leftType, Type rightType) => $"{(leftType.FullName == "System.String" ? left : $"cast({left} as nvarchar)")} + {(rightType.FullName == "System.String" ? right : $"cast({right} as nvarchar)")}";
+		internal override string StringConcat(string[] objs, Type[] types) {
+			var sb = new StringBuilder();
+			var news = new string[objs.Length];
+			for (var a = 0; a < objs.Length; a++)
+				news[a] = types[a] == typeof(string) ? objs[a] : $"cast({objs[a]} as nvarchar)";
+			return string.Join(" + ", news);
+		}
 		internal override string Mod(string left, string right, Type leftType, Type rightType) => $"{left} % {right}";
 
 		internal override string QuoteWriteParamter(Type type, string paramterName) => paramterName;

FreeSql/Sqlite/SqliteExpression.cs

@@ -208,6 +208,8 @@ namespace FreeSql.Sqlite {
 					case "IsNullOrEmpty":
 						var arg1 = getExp(exp.Arguments[0]);
 						return $"({arg1} is null or {arg1} = '')";
+					case "Concat":
+						return _common.StringConcat(exp.Arguments.Select(a => getExp(a)).ToArray(), null);
 				}
 			} else {
 				var left = getExp(exp.Object);

FreeSql/Sqlite/SqliteUtils.cs

@@ -61,7 +61,7 @@ namespace FreeSql.Sqlite {
 		}
 		internal override string QuoteParamterName(string name) => $"@{(_orm.CodeFirst.IsSyncStructureToLower ? name.ToLower() : name)}";
 		internal override string IsNull(string sql, object value) => $"ifnull({sql}, {value})";
-		internal override string StringConcat(string left, string right, Type leftType, Type rightType) => $"{left} || {right}";
+		internal override string StringConcat(string[] objs, Type[] types) => $"{string.Join(" || ", objs)}";
 		internal override string Mod(string left, string right, Type leftType, Type rightType) => $"{left} % {right}";
 
 		internal override string QuoteWriteParamter(Type type, string paramterName) => paramterName;