diff --git a/FreeSql.DbContext/DbSet/DbSetAsync.cs b/FreeSql.DbContext/DbSet/DbSetAsync.cs
index 07123ef8..3d7df0bc 100644
--- a/FreeSql.DbContext/DbSet/DbSetAsync.cs
+++ b/FreeSql.DbContext/DbSet/DbSetAsync.cs
@@ -160,8 +160,7 @@ namespace FreeSql
                     await DbContextExecCommandAsync();
                     //删除没有保存的数据
                     var propValEach = GetItemValue(item, prop) as IEnumerable;
-                    await _db.Orm.Select<object>().AsType(tref.RefEntityType).WhereDynamic(propValEach, true)
-                        .ToDelete().ExecuteAffrowsAsync();
+                    await _db.Orm.Delete<object>().AsType(tref.RefEntityType).WhereDynamic(propValEach, true).ExecuteAffrowsAsync();
                 }
             }
             finally
diff --git a/FreeSql.DbContext/DbSet/DbSetSync.cs b/FreeSql.DbContext/DbSet/DbSetSync.cs
index 912c29ce..4e92feb7 100644
--- a/FreeSql.DbContext/DbSet/DbSetSync.cs
+++ b/FreeSql.DbContext/DbSet/DbSetSync.cs
@@ -172,8 +172,7 @@ namespace FreeSql
                     DbContextExecCommand();
                     //删除没有保存的数据
                     var propValEach = GetItemValue(item, prop) as IEnumerable;
-                    _db.Orm.Select<object>().AsType(tref.RefEntityType).WhereDynamic(propValEach, true)
-                        .ToDelete().ExecuteAffrows();
+                    _db.Orm.Delete<object>().AsType(tref.RefEntityType).WhereDynamic(propValEach, true).ExecuteAffrows();
                 }
             }
             finally
diff --git a/FreeSql.DbContext/FreeSql.DbContext.xml b/FreeSql.DbContext/FreeSql.DbContext.xml
index b718b2e5..d9f91124 100644
--- a/FreeSql.DbContext/FreeSql.DbContext.xml
+++ b/FreeSql.DbContext/FreeSql.DbContext.xml
@@ -110,6 +110,13 @@
             清空状态数据
             </summary>
         </member>
+        <member name="M:FreeSql.DbSet`1.RemoveAsync(System.Linq.Expressions.Expression{System.Func{`0,System.Boolean}})">
+            <summary>
+            根据 lambda 条件删除数据
+            </summary>
+            <param name="predicate"></param>
+            <returns></returns>
+        </member>
         <member name="M:FreeSql.DbSet`1.Add(`0)">
             <summary>
             添加
@@ -267,6 +274,18 @@
             此工作单元内的实体变化跟踪
             </summary>
         </member>
+        <member name="P:FreeSql.UnitOfWork.DebugBeingUsed">
+            <summary>
+            正在使用中的工作单元（调试）
+            </summary>
+        </member>
+        <member name="P:FreeSql.UnitOfWork.Id">
+            <summary>
+            开启事务后有值，是 UnitOfWork 的唯一标识<para></para>
+            格式：yyyyMMdd_HHmmss_种子id<para></para>
+            例如：20191121_214504_1
+            </summary>
+        </member>
         <member name="M:FreeSqlDbContextExtensions.CreateDbContext(IFreeSql)">
             <summary>
             创建普通数据上下文档对象
diff --git a/FreeSql.DbContext/UnitOfWork/UnitOfWork.cs b/FreeSql.DbContext/UnitOfWork/UnitOfWork.cs
index 892d5e74..4f619c71 100644
--- a/FreeSql.DbContext/UnitOfWork/UnitOfWork.cs
+++ b/FreeSql.DbContext/UnitOfWork/UnitOfWork.cs
@@ -1,6 +1,7 @@
 using SafeObjectPool;
 using System;
 using System.Collections.Generic;
+using System.Collections.Concurrent;
 using System.Data;
 using System.Data.Common;
 using System.Linq;
@@ -14,10 +15,23 @@ namespace FreeSql
         public static readonly AsyncLocal<IUnitOfWork> Current = new AsyncLocal<IUnitOfWork>();
 #endif
 
+        static int _seed;
+        /// <summary>
+        /// 正在使用中的工作单元（调试）
+        /// </summary>
+        public static ConcurrentDictionary<string, UnitOfWork> DebugBeingUsed { get; } = new ConcurrentDictionary<string, UnitOfWork>();
+
         protected IFreeSql _fsql;
         protected Object<DbConnection> _conn;
         protected DbTransaction _tran;
 
+        /// <summary>
+        /// 开启事务后有值，是 UnitOfWork 的唯一标识<para></para>
+        /// 格式：yyyyMMdd_HHmmss_种子id<para></para>
+        /// 例如：20191121_214504_1
+        /// </summary>
+        public string Id { get; private set; }
+
         public UnitOfWork(IFreeSql fsql)
         {
             _fsql = fsql;
@@ -28,6 +42,9 @@ namespace FreeSql
 
         void ReturnObject()
         {
+            if (string.IsNullOrEmpty(this.Id) == false && DebugBeingUsed.TryRemove(this.Id, out var old))
+                this.Id = null;
+
             _fsql.Ado.MasterPool.Return(_conn);
             _tran = null;
             _conn = null;
@@ -66,6 +83,9 @@ namespace FreeSql
                 _tran = IsolationLevel == null ?
                     _conn.Value.BeginTransaction() :
                     _conn.Value.BeginTransaction(IsolationLevel.Value);
+
+                this.Id = $"{DateTime.Now.ToString("yyyyMMdd_HHmmss")}_{Interlocked.Increment(ref _seed)}";
+                DebugBeingUsed.TryAdd(this.Id, this);
             }
             catch
             {
diff --git a/FreeSql/FreeSql.xml b/FreeSql/FreeSql.xml
index 6bc4b8d9..56b67dc0 100644
--- a/FreeSql/FreeSql.xml
+++ b/FreeSql/FreeSql.xml
@@ -655,11 +655,12 @@
             <param name="items">实体集合</param>
             <returns></returns>
         </member>
-        <member name="M:FreeSql.IDelete`1.WhereDynamic(System.Object)">
+        <member name="M:FreeSql.IDelete`1.WhereDynamic(System.Object,System.Boolean)">
             <summary>
             传入动态对象如：主键值 | new[]{主键值1,主键值2} | TEntity1 | new[]{TEntity1,TEntity2} | new{id=1}
             </summary>
             <param name="dywhere">主键值、主键值集合、实体、实体集合、匿名对象、匿名对象集合</param>
+            <param name="not">是否标识为NOT</param>
             <returns></returns>
         </member>
         <member name="M:FreeSql.IDelete`1.DisableGlobalFilter(System.String[])">
@@ -1797,11 +1798,12 @@
             <param name="items">实体集合</param>
             <returns></returns>
         </member>
-        <member name="M:FreeSql.IUpdate`1.WhereDynamic(System.Object)">
+        <member name="M:FreeSql.IUpdate`1.WhereDynamic(System.Object,System.Boolean)">
             <summary>
             传入动态对象如：主键值 | new[]{主键值1,主键值2} | TEntity1 | new[]{TEntity1,TEntity2} | new{id=1}
             </summary>
             <param name="dywhere">主键值、主键值集合、实体、实体集合、匿名对象、匿名对象集合</param>
+            <param name="not">是否标识为NOT</param>
             <returns></returns>
         </member>
         <member name="M:FreeSql.IUpdate`1.DisableGlobalFilter(System.String[])">
diff --git a/FreeSql/Interface/Curd/IDelete.cs b/FreeSql/Interface/Curd/IDelete.cs
index 127abd7a..3619cd67 100644
--- a/FreeSql/Interface/Curd/IDelete.cs
+++ b/FreeSql/Interface/Curd/IDelete.cs
@@ -52,8 +52,9 @@ namespace FreeSql
         /// 传入动态对象如：主键值 | new[]{主键值1,主键值2} | TEntity1 | new[]{TEntity1,TEntity2} | new{id=1}
         /// </summary>
         /// <param name="dywhere">主键值、主键值集合、实体、实体集合、匿名对象、匿名对象集合</param>
+        /// <param name="not">是否标识为NOT</param>
         /// <returns></returns>
-        IDelete<T1> WhereDynamic(object dywhere);
+        IDelete<T1> WhereDynamic(object dywhere, bool not = false);
 
         /// <summary>
         /// 禁用全局过滤功能，不传参数时将禁用所有
diff --git a/FreeSql/Interface/Curd/IUpdate.cs b/FreeSql/Interface/Curd/IUpdate.cs
index 2c47437d..9276c68d 100644
--- a/FreeSql/Interface/Curd/IUpdate.cs
+++ b/FreeSql/Interface/Curd/IUpdate.cs
@@ -121,8 +121,9 @@ namespace FreeSql
         /// 传入动态对象如：主键值 | new[]{主键值1,主键值2} | TEntity1 | new[]{TEntity1,TEntity2} | new{id=1}
         /// </summary>
         /// <param name="dywhere">主键值、主键值集合、实体、实体集合、匿名对象、匿名对象集合</param>
+        /// <param name="not">是否标识为NOT</param>
         /// <returns></returns>
-        IUpdate<T1> WhereDynamic(object dywhere);
+        IUpdate<T1> WhereDynamic(object dywhere, bool not = false);
 
         /// <summary>
         /// 禁用全局过滤功能，不传参数时将禁用所有
diff --git a/FreeSql/Internal/CommonProvider/DeleteProvider.cs b/FreeSql/Internal/CommonProvider/DeleteProvider.cs
index b1b740af..ed1bac84 100644
--- a/FreeSql/Internal/CommonProvider/DeleteProvider.cs
+++ b/FreeSql/Internal/CommonProvider/DeleteProvider.cs
@@ -96,7 +96,9 @@ namespace FreeSql.Internal.CommonProvider
         }
         public IDelete<T1> Where(T1 item) => this.Where(new[] { item });
         public IDelete<T1> Where(IEnumerable<T1> items) => this.Where(_commonUtils.WhereItems(_table, "", items));
-        public IDelete<T1> WhereDynamic(object dywhere) => this.Where(_commonUtils.WhereObject(_table, "", dywhere));
+        public IDelete<T1> WhereDynamic(object dywhere, bool not = false) => not == false ?
+            this.Where(_commonUtils.WhereObject(_table, "", dywhere)) :
+            this.Where($"not({_commonUtils.WhereObject(_table, "", dywhere)})");
 
         public IDelete<T1> DisableGlobalFilter(params string[] name)
         {
diff --git a/FreeSql/Internal/CommonProvider/UpdateProvider.cs b/FreeSql/Internal/CommonProvider/UpdateProvider.cs
index 8823c5bc..51c04727 100644
--- a/FreeSql/Internal/CommonProvider/UpdateProvider.cs
+++ b/FreeSql/Internal/CommonProvider/UpdateProvider.cs
@@ -434,7 +434,9 @@ namespace FreeSql.Internal.CommonProvider
         }
         public IUpdate<T1> Where(T1 item) => this.Where(new[] { item });
         public IUpdate<T1> Where(IEnumerable<T1> items) => this.Where(_commonUtils.WhereItems(_table, "", items));
-        public IUpdate<T1> WhereDynamic(object dywhere) => this.Where(_commonUtils.WhereObject(_table, "", dywhere));
+        public IUpdate<T1> WhereDynamic(object dywhere, bool not = false) => not == false ?
+            this.Where(_commonUtils.WhereObject(_table, "", dywhere)) :
+            this.Where($"not({_commonUtils.WhereObject(_table, "", dywhere)})");
 
         public IUpdate<T1> DisableGlobalFilter(params string[] name)
         {