完成初步的分表分页组件

samples/Sample.SqlServer/Controllers/ValuesController.cs

@@ -58,15 +58,15 @@ namespace Sample.SqlServer.Controllers
 
 
 
-            var sresultx11231 = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Age == 198198).Select(o => o.Id).Contains("1981");
+            //var sresultx11231 = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Age == 198198).Select(o => o.Id).Contains("1981");
-            var sresultx1121 = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").Sum(o => o.Age);
+            //var sresultx1121 = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").Sum(o => o.Age);
-            var sresultx111 = _defaultTableDbContext.Set<SysUserMod>().FirstOrDefault(o => o.Id == "198");
+            //var sresultx111 = _defaultTableDbContext.Set<SysUserMod>().FirstOrDefault(o => o.Id == "198");
-            var sresultx2 = _defaultTableDbContext.Set<SysUserMod>().Count(o => o.Age <= 10);
+            //var sresultx2 = _defaultTableDbContext.Set<SysUserMod>().Count(o => o.Age <= 10);
-            var sresultx = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").FirstOrDefault();
+            //var sresultx = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").FirstOrDefault();
-            var sresultx33 = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").Select(o => o.Id).FirstOrDefault();
+            //var sresultx33 = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").Select(o => o.Id).FirstOrDefault();
-            var sresultxc = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").Select(o => o.Id).ToList();
+            //var sresultxc = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").Select(o => o.Id).ToList();
-            var sresultxasdc = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").ToList();
+            //var sresultxasdc = _defaultTableDbContext.Set<SysUserMod>().Where(o => o.Id == "198").ToList();
-            var sresult = _defaultTableDbContext.Set<SysUserMod>().ToList();
+            //var sresult = _defaultTableDbContext.Set<SysUserMod>().ToList();
 
             var sysUserMod98 = result.FirstOrDefault(o => o.Id == "98");
             _defaultTableDbContext.Attach(sysUserMod98);
@@ -86,5 +86,11 @@ namespace Sample.SqlServer.Controllers
             }
             return Ok();
         }
+        [HttpGet]
+        public async Task<IActionResult> Get1([FromQuery] int p,[FromQuery]int s)
+        {
+            var shardingPageResultAsync = await _defaultTableDbContext.Set<SysUserSalary>().OrderByDescending(o=>o.DateOfMonth).ToShardingPageAsync(p, s);
+            return Ok(shardingPageResultAsync);
+        }
     }
 } 

samples/Sample.SqlServer/DIExtension.cs

@@ -1,6 +1,8 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.AspNetCore.Builder;
+using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.DependencyInjection;
 using Sample.SqlServer.DbContexts;
 using Sample.SqlServer.Domain.Entities;
@@ -25,14 +27,17 @@ namespace Sample.SqlServer
 
         public static void DbSeed(this IApplicationBuilder app)
         {
-            using (var scope=app.ApplicationServices.CreateScope())
+            using (var scope = app.ApplicationServices.CreateScope())
             {
-                var virtualDbContext =scope.ServiceProvider.GetService<DefaultShardingDbContext>();
+                var virtualDbContext = scope.ServiceProvider.GetService<DefaultShardingDbContext>();
                 if (!virtualDbContext.Set<SysUserMod>().Any())
                 {
                     var ids = Enumerable.Range(1, 1000);
                     var userMods = new List<SysUserMod>();
+                    var userSalaries = new List<SysUserSalary>();
                     var SysTests = new List<SysTest>();
+                    var beginTime = new DateTime(2020, 1, 1);
+                    var endTime = new DateTime(2021, 12, 1);
                     foreach (var id in ids)
                     {
                         userMods.Add(new SysUserMod()
@@ -40,16 +45,38 @@ namespace Sample.SqlServer
                             Id = id.ToString(),
                             Age = id,
                             Name = $"name_{id}",
+                            AgeGroup = Math.Abs(id % 10)
                         });
                         SysTests.Add(new SysTest()
                         {
                             Id = id.ToString(),
                             UserId = id.ToString()
                         });
+                        var tempTime = beginTime;
+                        var i = 0;
+                        while (tempTime <= endTime)
+                        {
+                            var dateOfMonth = $@"{tempTime:yyyyMM}";
+                            userSalaries.Add(new SysUserSalary()
+                            {
+                                Id = $@"{id}{dateOfMonth}",
+                                UserId = id.ToString(),
+                                DateOfMonth = int.Parse(dateOfMonth),
+                                Salary = 700000 + id * 100 * i,
+                                SalaryLong = 700000 + id * 100 * i,
+                                SalaryDecimal = (700000 + id * 100 * i) / 100m,
+                                SalaryDouble = (700000 + id * 100 * i) / 100d,
+                                SalaryFloat = (700000 + id * 100 * i) / 100f
+                            });
+                            tempTime = tempTime.AddMonths(1);
+                            i++;
+                        }
                     }
 
                     virtualDbContext.AddRange(userMods);
                     virtualDbContext.AddRange(SysTests);
+                    virtualDbContext.AddRange(userSalaries);
+
                     virtualDbContext.SaveChanges();
                 }
             }

samples/Sample.SqlServer/DbContexts/DefaultShardingDbContext.cs

@@ -19,6 +19,7 @@ namespace Sample.SqlServer.DbContexts
             base.OnModelCreating(modelBuilder);
             modelBuilder.ApplyConfiguration(new SysUserModMap());
             modelBuilder.ApplyConfiguration(new SysTestMap());
+            modelBuilder.ApplyConfiguration(new SysUserSalaryMap());
         }
 
         public override Type ShardingDbContextType => this.GetType();

samples/Sample.SqlServer/DbContexts/DefaultTableDbContext.cs

@@ -17,6 +17,7 @@ namespace Sample.SqlServer.DbContexts
             base.OnModelCreating(modelBuilder);
             modelBuilder.ApplyConfiguration(new SysUserModMap());
             modelBuilder.ApplyConfiguration(new SysTestMap());
+            modelBuilder.ApplyConfiguration(new SysUserSalaryMap());
         }
 
         public IRouteTail RouteTail { get; set; }

samples/Sample.SqlServer/Domain/Entities/SysUserMod.cs

@@ -27,5 +27,6 @@ namespace Sample.SqlServer.Domain.Entities
         /// 用户姓名
         /// </summary>
         public int Age { get; set; }
+        public int AgeGroup { get; set; }
     }
 }

samples/Sample.SqlServer/Domain/Entities/SysUserSalary.cs

@@ -0,0 +1,42 @@
+using ShardingCore.Core;
+
+namespace Sample.SqlServer.Domain.Entities
+{
+/*
+* @Author: xjm
+* @Description:
+* @Date: Monday, 01 February 2021 15:43:22
+* @Email: 326308290@qq.com
+*/
+    public class SysUserSalary:IShardingTable
+    {
+        public string Id { get; set; }
+        public string UserId { get; set; }
+        /// <summary>
+        /// 每月的金额
+        /// </summary>
+        [ShardingTableKey]
+        public int DateOfMonth { get; set; }
+        /// <summary>
+        /// 工资
+        /// </summary>
+        public int Salary { get; set; }
+        /// <summary>
+        /// 工资
+        /// </summary>
+        public long SalaryLong { get; set; }
+        
+        /// <summary>
+        /// 工资
+        /// </summary>
+        public decimal SalaryDecimal { get; set; }
+        /// <summary>
+        /// 工资
+        /// </summary>
+        public double SalaryDouble { get; set; }
+        /// <summary>
+        /// 工资
+        /// </summary>
+        public float SalaryFloat { get; set; }
+    }
+}

samples/Sample.SqlServer/Domain/Maps/SysUserSalaryMap.cs

@@ -0,0 +1,23 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+using Sample.SqlServer.Domain.Entities;
+
+namespace Sample.SqlServer.Domain.Maps
+{
+/*
+* @Author: xjm
+* @Description:
+* @Date: Monday, 01 February 2021 15:42:35
+* @Email: 326308290@qq.com
+*/
+    public class SysUserSalaryMap:IEntityTypeConfiguration<SysUserSalary>
+    {
+        public void Configure(EntityTypeBuilder<SysUserSalary> builder)
+        {
+            builder.HasKey(o => o.Id);
+            builder.Property(o => o.Id).IsRequired().HasMaxLength(128);
+            builder.Property(o => o.UserId).IsRequired().HasMaxLength(128);
+            builder.ToTable(nameof(SysUserSalary));
+        }
+    }
+}

samples/Sample.SqlServer/Shardings/SysUserModPaginationConfiguration.cs

@@ -12,7 +12,7 @@ namespace Sample.SqlServer.Shardings
         public void Configure(PaginationBuilder<SysUserMod> builder)
         {
             builder.PaginationSequence(o => o.Id)
-                .UseQueryMatch(PaginationMatchEnum.Owner | PaginationMatchEnum.Named | PaginationMatchEnum.FirstMatch);
+                .UseQueryMatch(PaginationMatchEnum.Owner | PaginationMatchEnum.Named | PaginationMatchEnum.PrimaryMatch);
         }
     }
 }

samples/Sample.SqlServer/Shardings/SysUserSalaryPaginationConfiguration.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using Sample.SqlServer.Domain.Entities;
+using ShardingCore.Sharding.PaginationConfigurations;
+
+namespace Sample.SqlServer.Shardings
+{
+    public class SysUserSalaryPaginationConfiguration:IPaginationConfiguration<SysUserSalary>
+    {
+        public void Configure(PaginationBuilder<SysUserSalary> builder)
+        {
+            //builder.PaginationSequence(o => o.Id)
+            //    .UseQueryMatch(PaginationMatchEnum.Owner | PaginationMatchEnum.Named | PaginationMatchEnum.PrimaryMatch);
+            //builder.PaginationSequence(o => o.DateOfMonth)
+            //    .UseQueryMatch(PaginationMatchEnum.Owner | PaginationMatchEnum.Named | PaginationMatchEnum.PrimaryMatch).UseAppendIfOrderNone();
+            builder.ConfigReverseShardingPage();
+        }
+    }
+}

samples/Sample.SqlServer/Shardings/SysUserSalaryVirtualTableRoute.cs

@@ -0,0 +1,80 @@
+using System;
+using System.Collections.Generic;
+using System.Linq.Expressions;
+using Sample.SqlServer.Domain.Entities;
+using ShardingCore.Core.VirtualRoutes;
+using ShardingCore.Core.VirtualRoutes.TableRoutes.Abstractions;
+using ShardingCore.Sharding.PaginationConfigurations;
+
+namespace Sample.SqlServer.Shardings
+{
+/*
+* @Author: xjm
+* @Description:
+* @Date: Monday, 01 February 2021 15:54:55
+* @Email: 326308290@qq.com
+*/
+    public class SysUserSalaryVirtualTableRoute:AbstractShardingOperatorVirtualTableRoute<SysUserSalary,int>
+    {
+        protected override int ConvertToShardingKey(object shardingKey)
+        {
+            return Convert.ToInt32(shardingKey);
+        }
+
+        public override string ShardingKeyToTail(object shardingKey)
+        {
+            var time = ConvertToShardingKey(shardingKey);
+            return TimeFormatToTail(time);
+        }
+
+
+        public override List<string> GetAllTails()
+        {
+            var beginTime = new DateTime(2020, 1, 1);
+            var endTime = new DateTime(2021, 12, 1);
+            var list = new List<string>(24);
+            var tempTime = beginTime;
+            while (tempTime <= endTime)
+            {
+                list.Add($"{tempTime:yyyyMM}");
+                tempTime = tempTime.AddMonths(1);
+            }
+
+            return list;
+        }
+
+        protected  string TimeFormatToTail(int time)
+        {
+            var dateOfMonth=DateTime.ParseExact($"{time}","yyyyMM",System.Globalization.CultureInfo.InvariantCulture,System.Globalization.DateTimeStyles.AdjustToUniversal);
+            return $"{dateOfMonth:yyyyMM}";
+        }
+
+        protected override Expression<Func<string, bool>> GetRouteToFilter(int shardingKey, ShardingOperatorEnum shardingOperator)
+        {
+            var t = TimeFormatToTail(shardingKey);
+            switch (shardingOperator)
+            {
+                case ShardingOperatorEnum.GreaterThan:
+                case ShardingOperatorEnum.GreaterThanOrEqual:
+                    return tail => String.Compare(tail, t, StringComparison.Ordinal) >= 0;
+                case ShardingOperatorEnum.LessThan:
+                    return tail => String.Compare(tail, t, StringComparison.Ordinal) < 0;
+                case ShardingOperatorEnum.LessThanOrEqual:
+                    return tail => String.Compare(tail, t, StringComparison.Ordinal) <= 0;
+                case ShardingOperatorEnum.Equal: return tail => tail == t;
+                default:
+                {
+#if DEBUG
+                    Console.WriteLine($"shardingOperator is not equal scan all table tail");
+#endif
+                    return tail => true;
+                }
+            }
+        }
+
+        public override IPaginationConfiguration<SysUserSalary> CreatePaginationConfiguration()
+        {
+            return new SysUserSalaryPaginationConfiguration();
+        }
+    }
+}

samples/Sample.SqlServer/Startup.cs

@@ -38,6 +38,7 @@ namespace Sample.SqlServer
                              //.ReplaceService<IQueryTranslationPostprocessorFactory,SqlServer2008QueryTranslationPostprocessorFactory>()//支持sqlserver2008r2
                              );//使用链接字符串创建dbcontext
                      op.AddShardingTableRoute<SysUserModVirtualTableRoute>();
+                     op.AddShardingTableRoute<SysUserSalaryVirtualTableRoute>();
                  });
 
             ////不支持MARS不支持追踪的

src/ShardingCore/Extensions/IShardingQueryableExtension.cs

@@ -1,6 +1,7 @@
 using System.Linq;
 using Microsoft.EntityFrameworkCore;
 using ShardingCore.Core.Internal.Visitors;
+using ShardingCore.Sharding.Visitors;
 
 namespace ShardingCore.Extensions
 {
@@ -29,7 +30,8 @@ namespace ShardingCore.Extensions
         /// <returns></returns>
         internal static IQueryable<T> RemoveSkip<T>(this IQueryable<T> source)
         {
-            return (IQueryable<T>)source.Provider.CreateQuery(new RemoveSkipVisitor().Visit(source.Expression));
+            var expression = new RemoveSkipVisitor().Visit(source.Expression);
+            return (IQueryable<T>)source.Provider.CreateQuery(expression);
         }
 
         /// <summary>
@@ -43,6 +45,17 @@ namespace ShardingCore.Extensions
             var expression = new RemoveTakeVisitor().Visit(source.Expression);
             return (IQueryable<T>) source.Provider.CreateQuery(expression);
         }
+        internal static IQueryable<T> RemoveOrderBy<T>(this IQueryable<T> source)
+        {
+            var expression = new RemoveOrderByVisitor().Visit(source.Expression);
+            return (IQueryable<T>) source.Provider.CreateQuery(expression);
+        }
+        
+        internal static IQueryable<T> RemoveOrderByDescending<T>(this IQueryable<T> source)
+        {
+            var expression = new RemoveOrderByDescendingVisitor().Visit(source.Expression);
+            return (IQueryable<T>) source.Provider.CreateQuery(expression);
+        }
 
         /// <summary>
         /// 切换数据源,保留原数据源中的Expression

src/ShardingCore/Extensions/InternalExtensions/InternalLinqExtension.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Text;
+
+namespace ShardingCore.Extensions.InternalExtensions
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 10:13:07
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    internal static class InternalLinqExtension
+    {
+        public static IEnumerable<TShource> OrderByIf<TShource, TKey>(this IEnumerable<TShource> source, Func<TShource, TKey> keySelector, bool condition,
+            IComparer<TKey>? comparer)
+        {
+            return condition ? source.OrderBy(keySelector, comparer) : source;
+        }
+        public static IEnumerable<TShource> OrderByDescendingIf<TShource, TKey>(this IEnumerable<TShource> source, Func<TShource, TKey> keySelector, bool condition,
+            IComparer<TKey>? comparer)
+        {
+            return condition ? source.OrderByDescending(keySelector, comparer) : source;
+        }
+    }
+}

src/ShardingCore/Extensions/InternalExtensions/InternalPaginationMetadataExtension.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using ShardingCore.Sharding.PaginationConfigurations;
+
+namespace ShardingCore.Extensions.InternalExtensions
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 13:21:09
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    internal  static class InternalPaginationMetadataExtension
+    {
+        internal static bool IsUseReverse(this PaginationMetadata paginationMetadata,int skip,long total)
+        {
+            if (total < paginationMetadata.ReverseTotalGe)
+                return false;
+
+            return paginationMetadata.ReverseFactor * total < skip;
+        }
+    }
+}

src/ShardingCore/Extensions/ObjectExtension.cs

@@ -72,6 +72,17 @@ namespace ShardingCore.Extensions
                 return null;
             }
         }
+        /// <summary>
+        /// 类型X是否包含某个属性
+        /// </summary>
+        /// <param name="type"></param>
+        /// <param name="propertyName"></param>
+        /// <returns></returns>
+        public static bool ContainPropertyName(this Type type, string propertyName)
+        {
+            var property = type.GetProperty(propertyName, _bindingFlags);
+            return property != null;
+        }
 
     }
 }

src/ShardingCore/Extensions/ShardingQueryableExtension.cs

@@ -0,0 +1,60 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.EntityFrameworkCore;
+using ShardingCore.Core.ShardingPage.Abstractions;
+
+namespace ShardingCore.Extensions
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 10:36:51
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    public static class ShardingQueryableExtension
+    {
+        public static async Task<ShardingPagedResult<T>> ToShardingPageAsync<T>(this IQueryable<T> source, int pageIndex, int pageSize)
+        {
+            //设置每次获取多少页
+            var take = pageSize <= 0 ? 1 : pageSize;
+            //设置当前页码最小1
+            var index = pageIndex <= 0 ? 1 : pageIndex;
+            //需要跳过多少页
+            var skip = (index - 1) * take;
+            var shardingPageManager = ShardingContainer.GetService<IShardingPageManager>();
+            using (shardingPageManager.CreateScope())
+            {
+                //获取每次总记录数
+                var count = await source.LongCountAsync();
+                if (count <= skip)
+                    return new ShardingPagedResult<T>(new List<T>(0), count);
+                var data = await source.Skip(skip).Take(take).ToListAsync();
+                return new ShardingPagedResult<T>(data, count);
+            }
+        }
+        public static ShardingPagedResult<T> ToShardingPage<T>(this IQueryable<T> source, int pageIndex, int pageSize)
+        {
+            //设置每次获取多少页
+            var take = pageSize <= 0 ? 1 : pageSize;
+            //设置当前页码最小1
+            var index = pageIndex <= 0 ? 1 : pageIndex;
+            //需要跳过多少页
+            var skip = (index - 1) * take;
+
+            var shardingPageManager = ShardingContainer.GetService<IShardingPageManager>();
+            using (shardingPageManager.CreateScope())
+            {
+                //获取每次总记录数
+                var count = source.Count();
+                if (count <= skip)
+                    return new ShardingPagedResult<T>(new List<T>(0), count);
+                var data = source.Skip(skip).Take(take).ToList();
+                return new ShardingPagedResult<T>(data, count);
+            }
+        }
+    }
+}

src/ShardingCore/Extensions/TaskExtension.cs

@@ -134,125 +134,4 @@ namespace ShardingCore.Extensions
             }
         }
     }
-}
+}
-static class TaskExtension
-{
-    /// <summary>
-    /// 是否成功
-    /// </summary>
-    /// <param name="task"></param>
-    /// <returns></returns>
-    public static bool IsCompletedSuccessfully(this Task task)
-    {
-        return task.IsCompleted && !(task.IsCanceled || task.IsFaulted);
-    }
-
-
-
-    /// <summary>
-    /// Waits for the task to complete, unwrapping any exceptions.
-    /// </summary>
-    /// <param name="task">The task. May not be <c>null</c>.</param>
-    public static void WaitAndUnwrapException(this Task task)
-    {
-        if (task == null)
-            throw new ArgumentNullException(nameof(task));
-        task.GetAwaiter().GetResult();
-    }
-
-    /// <summary>
-    /// Waits for the task to complete, unwrapping any exceptions.
-    /// </summary>
-    /// <param name="task">The task. May not be <c>null</c>.</param>
-    /// <param name="cancellationToken">A cancellation token to observe while waiting for the task to complete.</param>
-    /// <exception cref="OperationCanceledException">The <paramref name="cancellationToken"/> was cancelled before the <paramref name="task"/> completed, or the <paramref name="task"/> raised an <see cref="OperationCanceledException"/>.</exception>
-    public static void WaitAndUnwrapException(this Task task, CancellationToken cancellationToken)
-    {
-        if (task == null)
-            throw new ArgumentNullException(nameof(task));
-        try
-        {
-            task.Wait(cancellationToken);
-        }
-        catch (AggregateException ex)
-        {
-            ExceptionDispatchInfo.Capture(ex).Throw();
-            throw ex;
-        }
-    }
-
-    /// <summary>
-    /// Waits for the task to complete, unwrapping any exceptions.
-    /// </summary>
-    /// <typeparam name="TResult">The type of the result of the task.</typeparam>
-    /// <param name="task">The task. May not be <c>null</c>.</param>
-    /// <returns>The result of the task.</returns>
-    public static TResult WaitAndUnwrapException<TResult>(this Task<TResult> task)
-    {
-        if (task == null)
-            throw new ArgumentNullException(nameof(task));
-        return task.GetAwaiter().GetResult();
-    }
-
-    /// <summary>
-    /// Waits for the task to complete, unwrapping any exceptions.
-    /// </summary>
-    /// <typeparam name="TResult">The type of the result of the task.</typeparam>
-    /// <param name="task">The task. May not be <c>null</c>.</param>
-    /// <param name="cancellationToken">A cancellation token to observe while waiting for the task to complete.</param>
-    /// <returns>The result of the task.</returns>
-    /// <exception cref="OperationCanceledException">The <paramref name="cancellationToken"/> was cancelled before the <paramref name="task"/> completed, or the <paramref name="task"/> raised an <see cref="OperationCanceledException"/>.</exception>
-    public static TResult WaitAndUnwrapException<TResult>(this Task<TResult> task, CancellationToken cancellationToken)
-    {
-        if (task == null)
-            throw new ArgumentNullException(nameof(task));
-        try
-        {
-            task.Wait(cancellationToken);
-            return task.Result;
-        }
-        catch (AggregateException ex)
-        {
-            ExceptionDispatchInfo.Capture(ex).Throw();
-            throw ex;
-        }
-    }
-
-    /// <summary>
-    /// Waits for the task to complete, but does not raise task exceptions. The task exception (if any) is unobserved.
-    /// </summary>
-    /// <param name="task">The task. May not be <c>null</c>.</param>
-    public static void WaitWithoutException(this Task task)
-    {
-        if (task == null)
-            throw new ArgumentNullException(nameof(task));
-        try
-        {
-            task.Wait();
-        }
-        catch (AggregateException)
-        {
-        }
-    }
-
-    /// <summary>
-    /// Waits for the task to complete, but does not raise task exceptions. The task exception (if any) is unobserved.
-    /// </summary>
-    /// <param name="task">The task. May not be <c>null</c>.</param>
-    /// <param name="cancellationToken">A cancellation token to observe while waiting for the task to complete.</param>
-    /// <exception cref="OperationCanceledException">The <paramref name="cancellationToken"/> was cancelled before the <paramref name="task"/> completed.</exception>
-    public static void WaitWithoutException(this Task task, CancellationToken cancellationToken)
-    {
-        if (task == null)
-            throw new ArgumentNullException(nameof(task));
-        try
-        {
-            task.Wait(cancellationToken);
-        }
-        catch (AggregateException)
-        {
-            cancellationToken.ThrowIfCancellationRequested();
-        }
-    }
-}
-}

src/ShardingCore/Sharding/Enumerators/StreamMergeAsync/InMemoryReverseStreamMergeAsyncEnumerator.cs

@@ -0,0 +1,61 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ShardingCore.Sharding.Enumerators.StreamMergeAsync
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 15:30:32
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    public class InMemoryReverseStreamMergeAsyncEnumerator<T>:IStreamMergeAsyncEnumerator<T>
+    {
+        private readonly IStreamMergeAsyncEnumerator<T> _inMemoryStreamMergeAsyncEnumerator;
+        private bool _first = true;
+        private IEnumerator<T> _reverseEnumerator = Enumerable.Empty<T>().GetEnumerator();
+        public InMemoryReverseStreamMergeAsyncEnumerator(IStreamMergeAsyncEnumerator<T> inMemoryStreamMergeAsyncEnumerator)
+        {
+            _inMemoryStreamMergeAsyncEnumerator = inMemoryStreamMergeAsyncEnumerator;
+        }
+        public async ValueTask DisposeAsync()
+        {
+            await _inMemoryStreamMergeAsyncEnumerator.DisposeAsync();
+            _reverseEnumerator.Dispose();
+        }
+
+        public async ValueTask<bool> MoveNextAsync()
+        {
+            if (_first)
+            {
+                ICollection<T> _reverseCollection = new LinkedList<T>();
+                while(await _inMemoryStreamMergeAsyncEnumerator.MoveNextAsync())
+                {
+                    _reverseCollection.Add(_inMemoryStreamMergeAsyncEnumerator.Current);
+                }
+
+                _reverseEnumerator = _reverseCollection.Reverse().GetEnumerator();
+                _first = false;
+            }
+
+            return _reverseEnumerator.MoveNext();
+        }
+
+        public T Current => _reverseEnumerator.Current;
+        public bool SkipFirst()
+        {
+            throw new NotImplementedException();
+        }
+
+        public bool HasElement()
+        {
+            throw new NotImplementedException();
+        }
+
+        public T ReallyCurrent => Current;
+    }
+}

src/ShardingCore/Sharding/PaginationConfigurations/PaginationBuilder.cs

@@ -32,13 +32,15 @@ namespace ShardingCore.Sharding.PaginationConfigurations
             return new PaginationOrderPropertyBuilder(orderPropertyExpression, _metadata);
         }
         /// <summary>
-        /// 配置当跳过多少条后开始启用只能分页
+        /// 配置反向排序 仅支持单排序 当skip>= reverseTotalGe*reverseFactor使用反向排序
         /// </summary>
-        /// <param name="skip"></param>
+        /// <param name="reverseFactor"></param>
+        /// <param name="reverseTotalGe"></param>
         /// <returns></returns>
-        public PaginationBuilder<TEntity> ConfigUseShardingPageIfGeSkip(long skip)
+        public PaginationBuilder<TEntity> ConfigReverseShardingPage(double reverseFactor=0.5,long reverseTotalGe=10000L)
         {
-            _metadata.UseShardingPageIfGeSkipAvg = skip;
+            _metadata.ReverseFactor = reverseFactor;
+            _metadata.ReverseTotalGe = reverseTotalGe;
             return this;
         }
         /// <summary>

src/ShardingCore/Sharding/PaginationConfigurations/PaginationConfig.cs

@@ -30,10 +30,15 @@ namespace ShardingCore.Sharding.PaginationConfigurations
         public IComparer<string> TailComparer { get; set; }
         public PaginationMatchEnum PaginationMatchEnum { get; set; }
         public PropertyInfo OrderPropertyInfo { get; set; }
+
         /// <summary>
         /// 如果查询没发现排序就将当前配置追加上去
         /// </summary>
-        public bool AppendIfOrderNone { get; set; }
+        public bool AppendIfOrderNone => AppendOrder >= 0;
+        /// <summary>
+        /// 大于等于0表示需要
+        /// </summary>
+        public int AppendOrder { get; set; } = -1;
         public string PropertyName { get;}
 
 

src/ShardingCore/Sharding/PaginationConfigurations/PaginationMatchEnum.cs

@@ -22,6 +22,6 @@ namespace ShardingCore.Sharding.PaginationConfigurations
         /// <summary>
         /// 仅第一个匹配就可以了
         /// </summary>
-        FirstMatch = 1 << 2
+        PrimaryMatch = 1 << 2
     }
 }

src/ShardingCore/Sharding/PaginationConfigurations/PaginationMetadata.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Text;
 
 namespace ShardingCore.Sharding.PaginationConfigurations
@@ -17,10 +18,20 @@ namespace ShardingCore.Sharding.PaginationConfigurations
     public class  PaginationMetadata
     {
         public ISet<PaginationConfig> PaginationConfigs = new HashSet<PaginationConfig>();
+
         /// <summary>
-        /// 配置生效当跳过多少条后  GREATER THAN OR EQUAL
+        /// 反向排序因子
         /// </summary>
-        public long UseShardingPageIfGeSkipAvg { get; set; } = 3000L;
+        public double ReverseFactor { get; set; } = -1;
+
+        /// <summary>
+        /// 当条数大于多少条后采用反向排序
+        /// </summary>
+        public long ReverseTotalGe { get; set; } = 10000L;
+        /// <summary>
+        /// 是否已开启反向排序 仅支持单排序
+        /// </summary>
+        public bool EnableReverseShardingPage => ReverseFactor > 0 && ReverseFactor < 1 && ReverseTotalGe >= 1000;
         /// <summary>
         /// 分表发现如果少于多少条后直接取到内存 LESS THAN OR EQUAL
         /// </summary>

src/ShardingCore/Sharding/PaginationConfigurations/PaginationOrderPropertyBuilder.cs

@@ -44,10 +44,11 @@ namespace ShardingCore.Sharding.PaginationConfigurations
         /// <summary>
         /// 如果查询没发现排序就将当前配置追加上去
         /// </summary>
+        /// <param name="order">大于等于0生效,越大优先级越高</param>
         /// <returns></returns>
-        public PaginationOrderPropertyBuilder UseAppendIfOrderNone()
+        public PaginationOrderPropertyBuilder UseAppendIfOrderNone(int order=0)
         {
-            _paginationConfig.AppendIfOrderNone = true;
+            _paginationConfig.AppendOrder = order;
             return this;
         }
     }

src/ShardingCore/Sharding/ShardingQueryExecutors/AbstractShardingQueryExecutor.cs

@@ -1,36 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq.Expressions;
-using System.Text;
-using ShardingCore.Sharding.Abstractions;
-
-namespace ShardingCore.Sharding.ShardingQueryExecutors
-{
-    /*
-    * @Author: xjm
-    * @Description:
-    * @Date: 2021/8/30 17:11:40
-    * @Ver: 1.0
-    * @Email: 326308290@qq.com
-    */
-    public class AbstractShardingQueryExecutor<TEntity>: IShardingQueryExecutor<TEntity>
-    {
-        private readonly MethodCallExpression _expression;
-        private readonly IShardingDbContext _shardingDbContext;
-
-        public AbstractShardingQueryExecutor(MethodCallExpression expression,IShardingDbContext shardingDbContext)
-        {
-            _expression = expression;
-            _shardingDbContext = shardingDbContext;
-        }
-        public MethodCallExpression GetQueryExpression()
-        {
-            return _expression;
-        }
-
-        public IShardingDbContext GetCurrentShardingDbContext()
-        {
-            return _shardingDbContext;
-        }
-    }
-}

src/ShardingCore/Sharding/ShardingQueryExecutors/EnumeratorShardingQueryExecutor.cs

@@ -4,9 +4,11 @@ using System.Linq;
 using System.Linq.Expressions;
 using System.Text;
 using System.Threading;
+using ShardingCore.Core.Internal.Visitors;
 using ShardingCore.Core.ShardingPage.Abstractions;
 using ShardingCore.Core.VirtualTables;
 using ShardingCore.Extensions;
+using ShardingCore.Extensions.InternalExtensions;
 using ShardingCore.Sharding.Abstractions;
 using ShardingCore.Sharding.PaginationConfigurations;
 using ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines;
@@ -41,33 +43,76 @@ namespace ShardingCore.Sharding.ShardingQueryExecutors
                 return new SingleQueryEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext);
             }
             //未开启系统分表或者本次查询涉及多张分表
-            if (!_streamMergeContext.IsPaginationQuery()||!_streamMergeContext.IsSingleShardingTableQuery()||_shardingPageManager.Current == null)
+            if (_streamMergeContext.IsPaginationQuery()&&_streamMergeContext.IsSingleShardingTableQuery()&&_shardingPageManager.Current != null)
             {
-                return new DefaultShardingEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext);
+                //获取虚拟表判断是否启用了分页配置
-            }
+                var shardingEntityType = _streamMergeContext.RouteResults.First().ReplaceTables.First().EntityType;
-            var shardingEntityType = _streamMergeContext.RouteResults.First().ReplaceTables.Single(o=>o.IsShardingTable()).EntityType;
+                var virtualTable = _virtualTableManager.GetVirtualTable(_streamMergeContext.GetShardingDbContext().ShardingDbContextType, shardingEntityType);
-            var virtualTable = _virtualTableManager.GetVirtualTable(_streamMergeContext.GetShardingDbContext().ShardingDbContextType,shardingEntityType);
+                if (virtualTable.EnablePagination)
-            if (!virtualTable.EnablePagination)
-                return new DefaultShardingEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext);
-            if (_streamMergeContext.Orders.IsEmpty())
-            {
-                var append = virtualTable.PaginationMetadata.PaginationConfigs.FirstOrDefault(o=>o.AppendIfOrderNone);
-                if (append != null)
                 {
-                    123
+                    var paginationMetadata = virtualTable.PaginationMetadata;
-                    return new SequenceEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext);
+                    //判断本次查询的排序是否包含order，如果不包含就获取默认添加的排序
+                    if (_streamMergeContext.Orders.IsEmpty())
+                    {
+                        //除了判断属性名还要判断所属关系
+                        var appendPaginationConfig = paginationMetadata.PaginationConfigs.OrderByDescending(o=>o.AppendOrder)
+                            .FirstOrDefault(o => o.AppendIfOrderNone&&typeof(TEntity).ContainPropertyName(o.PropertyName)&& PaginationMatch(o));
+                        if (appendPaginationConfig != null)
+                        {
+                            return new AppenOrderSequenceEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext, appendPaginationConfig, _shardingPageManager.Current.RouteQueryResults);
+                        }
+                    }
+                    else
+                    {
+                        var primaryOrder = _streamMergeContext.Orders.First();
+                        var appendPaginationConfig = paginationMetadata.PaginationConfigs.FirstOrDefault(o => PaginationMatch(o,primaryOrder));
+                        if (appendPaginationConfig != null)
+                        {
+                            return new SequenceEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext, appendPaginationConfig, _shardingPageManager.Current.RouteQueryResults, primaryOrder.IsAsc);
+                        }
+                        if (_streamMergeContext.Orders.Count() == 1)
+                        {
+                            //skip过大reserve skip
+                            if (paginationMetadata.EnableReverseShardingPage &&_streamMergeContext.Take.GetValueOrDefault()>0)
+                            {
+                                var total = _shardingPageManager.Current.RouteQueryResults.Sum(o => o.QueryResult);
+                                if (paginationMetadata.IsUseReverse(_streamMergeContext.Skip.GetValueOrDefault(), total))
+                                {
+                                    return new ReverseShardingEnumeratorAsyncStreamMergeEngine<TEntity>(
+                                        _streamMergeContext, primaryOrder, total);
+                                }
+                            }
+                        }
+                    }
                 }
             }
 
-            var propertyOrder = _streamMergeContext.Orders.First();
+
-            //PaginationMatchEnum.Owner
+            return new DefaultShardingEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext);
-            111
+        }
-            var paginationConfig = virtualTable.PaginationMetadata.PaginationConfigs.FirstOrDefault(o=>o.PropertyName==propertyOrder.PropertyExpression);
+
-            if (paginationConfig==null)
+        private bool PaginationMatch(PaginationConfig paginationConfig)
-                return new DefaultShardingEnumeratorAsyncStreamMergeEngine<TEntity>(_streamMergeContext);
+        {
-            //调用顺序排序
+            if (paginationConfig.PaginationMatchEnum.HasFlag(PaginationMatchEnum.Owner)&& !paginationConfig.PaginationMatchEnum.HasFlag(PaginationMatchEnum.Named))
-            paginationConfig
+                return typeof(TEntity) == paginationConfig.OrderPropertyInfo.DeclaringType;
-            
+      
+            return false;
+        }
+        private bool PaginationMatch(PaginationConfig paginationConfig,PropertyOrder propertyOrder)
+        {
+            if (paginationConfig.PaginationMatchEnum.HasFlag(PaginationMatchEnum.PrimaryMatch))
+            {
+                if (!propertyOrder.PropertyExpression.StartsWith(paginationConfig.PropertyName))
+                    return false;
+            }
+
+            if (propertyOrder.PropertyExpression != paginationConfig.PropertyName)
+                return false;
+
+            if (paginationConfig.PaginationMatchEnum.HasFlag(PaginationMatchEnum.Owner)&&!paginationConfig.PaginationMatchEnum.HasFlag(PaginationMatchEnum.Named))
+                return typeof(TEntity) == paginationConfig.OrderPropertyInfo.DeclaringType;
+
+            return false;
         }
 
     }

src/ShardingCore/Sharding/StreamMergeContext.cs

@@ -31,7 +31,7 @@ namespace ShardingCore.Sharding
         //public DataSourceRoutingResult RoutingResult { get; }
         public int? Skip { get;}
         public int? Take { get; }
-        public IEnumerable<PropertyOrder> Orders { get;}
+        public IEnumerable<PropertyOrder> Orders { get; private set; }
         
         public SelectContext SelectContext { get;}
         public GroupByContext GroupByContext { get; }
@@ -68,7 +68,10 @@ namespace ShardingCore.Sharding
         //    GroupByContext = reWriteResult.GroupByContext;
         //    _reWriteSource = reWriteResult.ReWriteQueryable;
         //}
-
+        public void ReSetOrders(IEnumerable<PropertyOrder> orders)
+        {
+            Orders = orders;
+        }
         public DbContext CreateDbContext(RouteResult routeResult)
         {
             var routeTail = _routeTailFactory.Create(routeResult);

src/ShardingCore/Sharding/StreamMergeEngines/Abstractions/AbstractInMemoryAsyncMergeEngine.cs

@@ -106,7 +106,7 @@ namespace ShardingCore.Sharding.StreamMergeEngines.Abstractions
 
         public List<TResult> Execute<TResult>(Func<IQueryable, TResult> efQuery, CancellationToken cancellationToken = new CancellationToken())
         {
-            var tableResult = _mergeContext.GetRouteResults();
+            var tableResult = _mergeContext.RouteResults;
             var enumeratorTasks = tableResult.Select(routeResult =>
             {
                 return Task.Run(() =>

src/ShardingCore/Sharding/StreamMergeEngines/AsyncEnumerableStreamMergeEngine.cs

@@ -11,6 +11,7 @@ using ShardingCore.Extensions;
 using ShardingCore.Sharding.Enumerators;
 using ShardingCore.Sharding.Enumerators.StreamMergeAsync;
 using ShardingCore.Sharding.Enumerators.StreamMergeSync;
+using ShardingCore.Sharding.ShardingQueryExecutors;
 
 #if EFCORE2
 using Microsoft.EntityFrameworkCore.Extensions.Internal;
@@ -24,15 +25,13 @@ namespace ShardingCore.Sharding.StreamMergeEngines
     * @Date: Saturday, 14 August 2021 22:07:28
     * @Email: 326308290@qq.com
     */
-    public class AsyncEnumerableStreamMergeEngine<T> : IAsyncEnumerable<T>, IEnumerable<T>, IDisposable
+    public class AsyncEnumerableStreamMergeEngine<T> : IAsyncEnumerable<T>, IEnumerable<T>
     {
         private readonly StreamMergeContext<T> _mergeContext;
-        private readonly ICollection<DbContext> _parllelDbbContexts;
 
         public AsyncEnumerableStreamMergeEngine(StreamMergeContext<T> mergeContext)
         {
             _mergeContext = mergeContext;
-            _parllelDbbContexts = new LinkedList<DbContext>();
         }
 
 
@@ -46,7 +45,8 @@ namespace ShardingCore.Sharding.StreamMergeEngines
         }
         public IAsyncEnumerator<T> GetAsyncEnumerator(CancellationToken cancellationToken = new CancellationToken())
         {
-            return GetShardingEnumerator();
+            return new EnumeratorShardingQueryExecutor<T>(_mergeContext).ExecuteAsync(cancellationToken)
+                .GetAsyncEnumerator(cancellationToken);
         }
 #endif
 
@@ -62,47 +62,7 @@ namespace ShardingCore.Sharding.StreamMergeEngines
             return GetShardingEnumerator();
         }
 #endif
-
+        
-        private IQueryable<T> CreateAsyncExecuteQueryable(RouteResult routeResult,int routeCount)
-        {
-            var shardingDbContext = _mergeContext.CreateDbContext(routeResult);
-            var useOriginal = routeCount>1;
-            _parllelDbbContexts.Add(shardingDbContext);
-            var newQueryable = (IQueryable<T>)(useOriginal?_mergeContext.GetReWriteQueryable():_mergeContext.GetOriginalQueryable())
-                .ReplaceDbContextQueryable(shardingDbContext);
-            return newQueryable;
-        }
-
-        private IAsyncEnumerator<T> GetShardingEnumerator()
-        {
-            var tableResult = _mergeContext.RouteResults;
-            var routeCount = tableResult.Count();
-            var enumeratorTasks = tableResult.Select(routeResult =>
-            {
-                return Task.Run(async () =>
-                {
-                    try
-                    {
-                        var newQueryable = CreateAsyncExecuteQueryable(routeResult, routeCount);
-
-                        var asyncEnumerator = await GetAsyncEnumerator(newQueryable);
-                        return new StreamMergeAsyncEnumerator<T>(asyncEnumerator);
-                    }
-                    catch (Exception e)
-                    {
-                        Console.WriteLine(e);
-                        throw;
-                    }
-                });
-            }).ToArray();
-
-            var streamEnumerators = Task.WhenAll(enumeratorTasks).GetAwaiter().GetResult();
-            if (routeCount>1&&_mergeContext.HasSkipTake())
-                return new PaginationStreamMergeAsyncEnumerator<T>(_mergeContext, streamEnumerators);
-            if (_mergeContext.HasGroupQuery())
-                return new MultiAggregateOrderStreamMergeAsyncEnumerator<T>(_mergeContext, streamEnumerators);
-            return new MultiOrderStreamMergeAsyncEnumerator<T>(_mergeContext, streamEnumerators);
-        }
 
 
         private IEnumerator<T> GetEnumerator(IQueryable<T> newQueryable)
@@ -114,33 +74,9 @@ namespace ShardingCore.Sharding.StreamMergeEngines
 
         public IEnumerator<T> GetEnumerator()
         {
-            var tableResult = _mergeContext.RouteResults;
-            var routeCount = tableResult.Count();
-            var enumeratorTasks = tableResult.Select(routeResult =>
-            {
-                return Task.Run(() =>
-                {
-                    try
-                    {
-                        var newQueryable = CreateAsyncExecuteQueryable(routeResult, routeCount);
 
-                        var enumerator = GetEnumerator(newQueryable);
+            return new EnumeratorShardingQueryExecutor<T>(_mergeContext).ExecuteAsync()
-                        return new StreamMergeEnumerator<T>(enumerator);
+                .GetEnumerator();
-                    }
-                    catch (Exception e)
-                    {
-                        Console.WriteLine(e);
-                        throw;
-                    }
-                });
-            }).ToArray();
-
-            var streamEnumerators = Task.WhenAll(enumeratorTasks).GetAwaiter().GetResult();
-            if (routeCount > 1 && _mergeContext.HasSkipTake())
-                return new PaginationStreamMergeEnumerator<T>(_mergeContext, streamEnumerators);
-            if (_mergeContext.HasGroupQuery())
-                return new MultiAggregateOrderStreamMergeEnumerator<T>(_mergeContext, streamEnumerators);
-            return new MultiOrderStreamMergeEnumerator<T>(_mergeContext, streamEnumerators);
         }
 
         IEnumerator IEnumerable.GetEnumerator()
@@ -148,22 +84,5 @@ namespace ShardingCore.Sharding.StreamMergeEngines
             return GetEnumerator();
         }
 
-        public void Dispose()
-        {
-            if (_parllelDbbContexts.IsNotEmpty())
-            {
-                _parllelDbbContexts.ForEach(o =>
-                {
-                    try
-                    {
-                        o.Dispose();
-                    }
-                    catch (Exception e)
-                    {
-                        Console.WriteLine(e);
-                    }
-                });
-            }
-        }
     }
 }

src/ShardingCore/Sharding/StreamMergeEngines/EnumeratorStreamMergeEngines/AppenOrderSequenceEnumeratorAsyncStreamMergeEngine.cs

@@ -0,0 +1,100 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using ShardingCore.Core.Internal.Visitors;
+using ShardingCore.Core.ShardingPage.Abstractions;
+using ShardingCore.Core.VirtualRoutes.TableRoutes.RoutingRuleEngine;
+using ShardingCore.Core.VirtualTables;
+using ShardingCore.Exceptions;
+using ShardingCore.Extensions;
+using ShardingCore.Sharding.Enumerators;
+using ShardingCore.Sharding.Enumerators.StreamMergeAsync;
+using ShardingCore.Sharding.PaginationConfigurations;
+using ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines.Abstractions;
+using ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines.Base;
+
+namespace ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 8:09:18
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    public class AppenOrderSequenceEnumeratorAsyncStreamMergeEngine<TEntity> : AbstractEnumeratorAsyncStreamMergeEngine<TEntity>
+    {
+        private readonly PaginationConfig _appendPaginationConfig;
+        private readonly ICollection<RouteQueryResult<long>> _routeQueryResults;
+        private IShardingPageManager _shardingPageManager;
+        private IVirtualTableManager _virtualTableManager;
+        public AppenOrderSequenceEnumeratorAsyncStreamMergeEngine(StreamMergeContext<TEntity> streamMergeContext, PaginationConfig appendPaginationConfig, ICollection<RouteQueryResult<long>> routeQueryResults) : base(streamMergeContext)
+        {
+            _appendPaginationConfig = appendPaginationConfig;
+            _routeQueryResults = routeQueryResults;
+            _shardingPageManager = ShardingContainer.GetService<IShardingPageManager>();
+            _virtualTableManager = ShardingContainer.GetService<IVirtualTableManager>();
+        }
+
+        public override IStreamMergeAsyncEnumerator<TEntity>[] GetDbStreamMergeAsyncEnumerators()
+        {
+            var noPaginationQueryable = StreamMergeContext.GetOriginalQueryable().RemoveSkip().RemoveTake();
+            var skip = StreamMergeContext.Skip.GetValueOrDefault();
+            if (skip < 0)
+                throw new ShardingCoreException("skip must ge 0");
+
+            var take = StreamMergeContext.Take;
+            if (take.HasValue&&take.Value <= 0)
+                throw new ShardingCoreException("take must gt 0");
+
+            var sortRouteResults = _routeQueryResults.Select(o => new
+            {
+                Tail = o.RouteResult.ReplaceTables.First().Tail,
+                RouteQueryResult = o
+            }).OrderBy(o => o.Tail, _appendPaginationConfig.TailComparer).ToList();
+            var skipCount = skip;
+
+            var sequenceResults = new SequencePaginationList(sortRouteResults.Select(o=>o.RouteQueryResult)).Skip(skip).Take(take).ToList();
+     
+            StreamMergeContext.ReSetOrders(new PropertyOrder[] { new PropertyOrder(_appendPaginationConfig.PropertyName, true) });
+            var enumeratorTasks = sequenceResults.Select(sequenceResult =>
+            {
+                var newQueryable = CreateAsyncExecuteQueryable(noPaginationQueryable, sequenceResult);
+                return Task.Run(async () =>
+                {
+                    try
+                    {
+                        var asyncEnumerator = await DoGetAsyncEnumerator(newQueryable);
+                        return new StreamMergeAsyncEnumerator<TEntity>(asyncEnumerator);
+                    }
+                    catch (Exception e)
+                    {
+                        Console.WriteLine(e);
+                        throw;
+                    }
+                });
+            }).ToArray();
+
+            var streamEnumerators = Task.WhenAll(enumeratorTasks).WaitAndUnwrapException();
+            return streamEnumerators;
+        }
+
+        private  IQueryable<TEntity> CreateAsyncExecuteQueryable(IQueryable<TEntity> noPaginationQueryable, SequenceResult sequenceResult)
+        {
+            var shardingDbContext = StreamMergeContext.CreateDbContext(sequenceResult.RouteResult);
+            DbContextQueryStore.TryAdd(sequenceResult.RouteResult, shardingDbContext);
+            var newQueryable = (IQueryable<TEntity>)(noPaginationQueryable.Skip(sequenceResult.Skip).Take(sequenceResult.Take).OrderWithExpression(new PropertyOrder[]{new PropertyOrder(_appendPaginationConfig.PropertyName,true)}))
+                .ReplaceDbContextQueryable(shardingDbContext);
+            return newQueryable;
+        }
+
+        public override IStreamMergeAsyncEnumerator<TEntity> GetStreamMergeAsyncEnumerator(IStreamMergeAsyncEnumerator<TEntity>[] streamsAsyncEnumerators)
+        {
+            if (StreamMergeContext.HasGroupQuery())
+                return new MultiAggregateOrderStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
+            return new MultiOrderStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
+        }
+    }
+}

src/ShardingCore/Sharding/StreamMergeEngines/EnumeratorStreamMergeEngines/Base/SequencePaginationList.cs

@@ -0,0 +1,101 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using ShardingCore.Core.VirtualRoutes.TableRoutes.RoutingRuleEngine;
+
+namespace ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines.Base
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 8:31:20
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    public class SequencePaginationList
+    {
+        private readonly IEnumerable<RouteQueryResult<long>> _routeQueryResults;
+        private long? _skip;
+        private long? _take;
+
+        public SequencePaginationList(IEnumerable<RouteQueryResult<long>> routeQueryResults)
+        {
+            _routeQueryResults = routeQueryResults;
+        }
+        public SequencePaginationList Skip(long? skip)
+        {
+            _skip = skip;
+            return this;
+        }
+        public SequencePaginationList Take(long? take)
+        {
+            _take = take;
+            return this;
+        }
+
+        public ICollection<SequenceResult> ToList()
+        {
+            ICollection<SequenceResult> routeResults = new LinkedList<SequenceResult>();
+
+            var currentSkip = _skip.GetValueOrDefault();
+            var currentTake = _take;
+            bool stopSkip = false;
+            bool needBreak = false;
+            foreach (var routeQueryResult in _routeQueryResults)
+            {
+                if (!stopSkip)
+                {
+                    if (routeQueryResult.QueryResult >= currentSkip)
+                    {
+                        stopSkip = true;
+                    }
+                    else
+                    {
+                        currentSkip = currentSkip - routeQueryResult.QueryResult;
+                        continue;
+                    }
+                }
+
+                var currentRealSkip = currentSkip;
+                var currentRealTake = routeQueryResult.QueryResult-currentSkip;
+                if (currentSkip != 0)
+                    currentSkip = 0;
+                if (currentTake.HasValue)
+                {
+                    if (currentTake.Value <= currentRealTake)
+                    {
+                        currentRealTake = currentTake.Value;
+                        needBreak = true;
+                    }
+                    else
+                    {
+                        currentRealTake = currentTake.Value-currentRealTake;
+                    }
+                }
+                var sequenceResult = new SequenceResult(currentRealSkip, currentRealTake, routeQueryResult.RouteResult);
+                routeResults.Add(sequenceResult);
+
+                if (needBreak)
+                    break;
+
+            }
+
+            return routeResults;
+        }
+    }
+    public class SequenceResult
+    {
+        public SequenceResult(long skip, long take, RouteResult routeResult)
+        {
+            Skip = (int)skip;
+            Take = (int)take;
+            RouteResult = routeResult;
+        }
+
+        public int Skip { get; }
+        public int Take { get; }
+
+        public RouteResult RouteResult { get; }
+    }
+}

src/ShardingCore/Sharding/StreamMergeEngines/EnumeratorStreamMergeEngines/ReverseShardingEnumeratorAsyncStreamMergeEngine.cs

@@ -0,0 +1,91 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using ShardingCore.Core.Internal.Visitors;
+using ShardingCore.Core.VirtualRoutes.TableRoutes.RoutingRuleEngine;
+using ShardingCore.Extensions;
+using ShardingCore.Sharding.Enumerators;
+using ShardingCore.Sharding.Enumerators.StreamMergeAsync;
+using ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines.Abstractions;
+
+namespace ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 13:32:12
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    public class ReverseShardingEnumeratorAsyncStreamMergeEngine<TEntity> : AbstractEnumeratorAsyncStreamMergeEngine<TEntity>
+    {
+        private readonly PropertyOrder _primaryOrder;
+        private readonly long _total;
+
+        public ReverseShardingEnumeratorAsyncStreamMergeEngine(StreamMergeContext<TEntity> streamMergeContext, PropertyOrder primaryOrder, long total) : base(streamMergeContext)
+        {
+            _primaryOrder = primaryOrder;
+            _total = total;
+        }
+
+        public override IStreamMergeAsyncEnumerator<TEntity>[] GetDbStreamMergeAsyncEnumerators()
+        {
+
+            var noPaginationNoOrderQueryable = _primaryOrder.IsAsc ? StreamMergeContext.GetOriginalQueryable().RemoveSkip().RemoveTake().RemoveOrderBy(): StreamMergeContext.GetOriginalQueryable().RemoveSkip().RemoveTake().RemoveOrderByDescending();
+            var skip = StreamMergeContext.Skip.GetValueOrDefault();
+            var take = StreamMergeContext.Take.GetValueOrDefault();
+            var realSkip = _total- take- skip;
+            var tableResult = StreamMergeContext.RouteResults;
+            var reverseOrderQueryable = noPaginationNoOrderQueryable.Skip((int)realSkip).Take((int)realSkip+take).OrderWithExpression(new List<PropertyOrder>()
+            {
+                new PropertyOrder( _primaryOrder.PropertyExpression,!_primaryOrder.IsAsc)
+            });
+            var enumeratorTasks = tableResult.Select(routeResult =>
+            {
+                var newQueryable = CreateAsyncExecuteQueryable(reverseOrderQueryable,routeResult);
+                return Task.Run(async () =>
+                {
+                    try
+                    {
+                        var asyncEnumerator = await DoGetAsyncEnumerator(newQueryable);
+                        return new StreamMergeAsyncEnumerator<TEntity>(asyncEnumerator);
+                    }
+                    catch (Exception e)
+                    {
+                        Console.WriteLine(e);
+                        throw;
+                    }
+                });
+            }).ToArray();
+
+            var streamEnumerators = Task.WhenAll(enumeratorTasks).WaitAndUnwrapException();
+            return streamEnumerators;
+        }
+
+        private IQueryable<TEntity> CreateAsyncExecuteQueryable(IQueryable<TEntity> reverseOrderQueryable, RouteResult routeResult)
+        {
+            var shardingDbContext = StreamMergeContext.CreateDbContext(routeResult);
+            DbContextQueryStore.TryAdd(routeResult, shardingDbContext);
+            var newQueryable = (IQueryable<TEntity>)reverseOrderQueryable
+                .ReplaceDbContextQueryable(shardingDbContext);
+            return newQueryable;
+        }
+
+        public override IStreamMergeAsyncEnumerator<TEntity> GetStreamMergeAsyncEnumerator(IStreamMergeAsyncEnumerator<TEntity>[] streamsAsyncEnumerators)
+        {
+            var doGetStreamMergeAsyncEnumerator = DoGetStreamMergeAsyncEnumerator(streamsAsyncEnumerators);
+            return new InMemoryReverseStreamMergeAsyncEnumerator<TEntity>(doGetStreamMergeAsyncEnumerator);
+        }
+
+        private IStreamMergeAsyncEnumerator<TEntity> DoGetStreamMergeAsyncEnumerator(IStreamMergeAsyncEnumerator<TEntity>[] streamsAsyncEnumerators)
+        {
+            if (StreamMergeContext.IsPaginationQuery())
+                return new PaginationStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
+            if (StreamMergeContext.HasGroupQuery())
+                return new MultiAggregateOrderStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
+            return new MultiOrderStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
+        }
+    }
+}

src/ShardingCore/Sharding/StreamMergeEngines/EnumeratorStreamMergeEngines/SequenceEnumeratorAsyncStreamMergeEngine.cs

@@ -3,14 +3,18 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
+using ShardingCore.Core.Internal.Visitors;
 using ShardingCore.Core.ShardingPage.Abstractions;
 using ShardingCore.Core.VirtualRoutes.TableRoutes.RoutingRuleEngine;
 using ShardingCore.Core.VirtualTables;
 using ShardingCore.Exceptions;
 using ShardingCore.Extensions;
+using ShardingCore.Extensions.InternalExtensions;
 using ShardingCore.Sharding.Enumerators;
 using ShardingCore.Sharding.Enumerators.StreamMergeAsync;
+using ShardingCore.Sharding.PaginationConfigurations;
 using ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines.Abstractions;
+using ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines.Base;
 
 namespace ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines
 {
@@ -23,47 +27,43 @@ namespace ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines
     */
     public class SequenceEnumeratorAsyncStreamMergeEngine<TEntity> : AbstractEnumeratorAsyncStreamMergeEngine<TEntity>
     {
-        private IShardingPageManager _shardingPageManager;
+        private readonly PaginationConfig _orderPaginationConfig;
-        private IVirtualTableManager _virtualTableManager;
+        private readonly ICollection<RouteQueryResult<long>> _routeQueryResults;
-        public SequenceEnumeratorAsyncStreamMergeEngine(StreamMergeContext<TEntity> streamMergeContext) : base(streamMergeContext)
+        private readonly bool _isAsc;
+        public SequenceEnumeratorAsyncStreamMergeEngine(StreamMergeContext<TEntity> streamMergeContext, PaginationConfig orderPaginationConfig, ICollection<RouteQueryResult<long>> routeQueryResults, bool isAsc) : base(streamMergeContext)
         {
-            _shardingPageManager = ShardingContainer.GetService<IShardingPageManager>();
+            _orderPaginationConfig = orderPaginationConfig;
-            _virtualTableManager = ShardingContainer.GetService<IVirtualTableManager>();
+            _routeQueryResults = routeQueryResults;
+            _isAsc = isAsc;
         }
 
         public override IStreamMergeAsyncEnumerator<TEntity>[] GetDbStreamMergeAsyncEnumerators()
         {
-            var routeQueryResults = _shardingPageManager.Current.RouteQueryResults.ToList();
+            var noPaginationQueryable = StreamMergeContext.GetOriginalQueryable().RemoveSkip().RemoveTake();
-            if (routeQueryResults.Any(o => o.RouteResult.ReplaceTables.Count(p=>p.IsShardingTable())!=1)
+            var skip = StreamMergeContext.Skip.GetValueOrDefault();
-                || routeQueryResults.HasDifference(o=>o.RouteResult.ReplaceTables.First().EntityType))
+            if (skip < 0)
-                throw new InvalidOperationException($"error sharding page:[{StreamMergeContext.GetOriginalQueryable().Expression.ShardingPrint()}]");
+                throw new ShardingCoreException("skip must ge 0");
-            var shardingEntityType = routeQueryResults[0].RouteResult.ReplaceTables.FirstOrDefault(o=>o.IsShardingTable()).EntityType;
-            var virtualTable = _virtualTableManager.GetVirtualTable(StreamMergeContext.GetShardingDbContext().ShardingDbContextType, shardingEntityType);
-            if (!virtualTable.EnablePagination)
-            {
-                throw new ShardingCoreException("not support Sequence enumerator");
-            }
 
-            if (base.StreamMergeContext.Orders.IsEmpty())
+            var take = StreamMergeContext.Take;
-            {
+            if (take.HasValue && take.Value <= 0)
-                var append = virtualTable.PaginationMetadata.PaginationConfigs.FirstOrDefault(o=>o.AppendIfOrderNone);
+                throw new ShardingCoreException("take must gt 0");
-                if (append != null)
-                {
-                    StreamMergeContext.GetOriginalQueryable().OrderBy("")
-                }
-            }
 
-
+            var sortRouteResults = _routeQueryResults.Select(o => new
-            var tableResult = StreamMergeContext.RouteResults;
-            var routeCount = tableResult.Count();
-            var enumeratorTasks = tableResult.Select(routeResult =>
             {
+                Tail = o.RouteResult.ReplaceTables.First().Tail,
+                RouteQueryResult = o
+            }).OrderByIf(o => o.Tail, _isAsc, _orderPaginationConfig.TailComparer)
+                .OrderByDescendingIf(o => o.Tail, !_isAsc, _orderPaginationConfig.TailComparer).ToList();
+
+            var sequenceResults = new SequencePaginationList(sortRouteResults.Select(o => o.RouteQueryResult)).Skip(skip).Take(take).ToList();
+
+            var enumeratorTasks = sequenceResults.Select(sequenceResult =>
+            {
+                var newQueryable = CreateAsyncExecuteQueryable(noPaginationQueryable, sequenceResult);
                 return Task.Run(async () =>
                 {
                     try
                     {
-                        var newQueryable = CreateAsyncExecuteQueryable(routeResult, routeCount);
-
                         var asyncEnumerator = await DoGetAsyncEnumerator(newQueryable);
                         return new StreamMergeAsyncEnumerator<TEntity>(asyncEnumerator);
                     }
@@ -75,23 +75,21 @@ namespace ShardingCore.Sharding.StreamMergeEngines.EnumeratorStreamMergeEngines
                 });
             }).ToArray();
 
-            var streamEnumerators = Task.WhenAll(enumeratorTasks).GetAwaiter().GetResult();
+            var streamEnumerators = Task.WhenAll(enumeratorTasks).WaitAndUnwrapException();
             return streamEnumerators;
         }
 
-        public override IQueryable<TEntity> CreateAsyncExecuteQueryable(RouteResult routeResult, int routeCount)
+        private IQueryable<TEntity> CreateAsyncExecuteQueryable(IQueryable<TEntity> noPaginationQueryable, SequenceResult sequenceResult)
         {
-            var shardingDbContext = StreamMergeContext.CreateDbContext(routeResult);
+            var shardingDbContext = StreamMergeContext.CreateDbContext(sequenceResult.RouteResult);
-            DbContextQueryStore.TryAdd(routeResult, shardingDbContext);
+            DbContextQueryStore.TryAdd(sequenceResult.RouteResult, shardingDbContext);
-            var newQueryable = (IQueryable<TEntity>)(_multiRouteQuery ? StreamMergeContext.GetReWriteQueryable() : StreamMergeContext.GetOriginalQueryable())
+            var newQueryable = (IQueryable<TEntity>)(noPaginationQueryable.Skip(sequenceResult.Skip).Take(sequenceResult.Take))
                 .ReplaceDbContextQueryable(shardingDbContext);
             return newQueryable;
         }
 
         public override IStreamMergeAsyncEnumerator<TEntity> GetStreamMergeAsyncEnumerator(IStreamMergeAsyncEnumerator<TEntity>[] streamsAsyncEnumerators)
         {
-            if (_multiRouteQuery && StreamMergeContext.HasSkipTake())
-                return new PaginationStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
             if (StreamMergeContext.HasGroupQuery())
                 return new MultiAggregateOrderStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);
             return new MultiOrderStreamMergeAsyncEnumerator<TEntity>(StreamMergeContext, streamsAsyncEnumerators);

src/ShardingCore/Sharding/Visitors/PropertyOrder.cs

@@ -1,3 +1,5 @@
+using System;
+
 namespace ShardingCore.Core.Internal.Visitors
 {
     /*

src/ShardingCore/Sharding/Visitors/QuerySelectDiscoverVisitor.cs

@@ -48,11 +48,11 @@ namespace ShardingCore.Core.Internal.Visitors
                     var method = methodCallExpression.Method;
                     if (method.Name == nameof(Queryable.Count) || method.Name == nameof(Queryable.Sum) || method.Name == nameof(Queryable.Max) || method.Name == nameof(Queryable.Min) || method.Name == nameof(Queryable.Average))
                     {
-                        _selectContext.SelectProperties.Add(new SelectProperty(node.Members[i].Name,true,method.Name));
+                        _selectContext.SelectProperties.Add(new SelectProperty(node.Members[i].DeclaringType, node.Members[i].Name,true,method.Name));
                         continue;
                     }
                 }
-                _selectContext.SelectProperties.Add(new SelectProperty(node.Members[i].Name,false,string.Empty));
+                _selectContext.SelectProperties.Add(new SelectProperty(node.Members[i].DeclaringType, node.Members[i].Name,false,string.Empty));
             }
             return base.VisitNew(node);
         }

src/ShardingCore/Sharding/Visitors/RemoveOrderByDescendingVisitor.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Text;
+
+namespace ShardingCore.Sharding.Visitors
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 15:05:27
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    internal class RemoveOrderByDescendingVisitor : ExpressionVisitor
+    {
+        protected override Expression VisitMethodCall(MethodCallExpression node)
+        {
+            if (node.Method.Name == nameof(Queryable.OrderByDescending))
+                return base.Visit(node.Arguments[0]);
+
+            return base.VisitMethodCall(node);
+        }
+    }
+}

src/ShardingCore/Sharding/Visitors/RemoveOrderByVisitor.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using System.Text;
+
+namespace ShardingCore.Sharding.Visitors
+{
+    /*
+    * @Author: xjm
+    * @Description:
+    * @Date: 2021/9/3 15:04:25
+    * @Ver: 1.0
+    * @Email: 326308290@qq.com
+    */
+    internal class RemoveOrderByVisitor : ExpressionVisitor
+    {
+        protected override Expression VisitMethodCall(MethodCallExpression node)
+        {
+            if (node.Method.Name == nameof(Queryable.OrderBy))
+                return base.Visit(node.Arguments[0]);
+
+            return base.VisitMethodCall(node);
+        }
+    }
+}

src/ShardingCore/Sharding/Visitors/Selects/SelectProperty.cs

@@ -10,13 +10,14 @@ namespace ShardingCore.Core.Internal.Visitors.Selects
     */
     public class SelectProperty
     {
-        public SelectProperty(string propertyName,bool isAggregateMethod,string aggregateMethod)
+        public SelectProperty( Type ownerType,string propertyName,bool isAggregateMethod,string aggregateMethod)
         {
+            OwnerType = ownerType;
             PropertyName = propertyName;
             IsAggregateMethod = isAggregateMethod;
             AggregateMethod = aggregateMethod;
         }
-
+        public Type OwnerType { get; }
         public string PropertyName { get; }
         public bool IsAggregateMethod { get; }
         public string AggregateMethod { get; }