- 增加 IInsert.ExecuteSqlBulkCopy 扩展方法执行 SqlBulkCopy 批量插入，在 FreeSql.Provider.SqlServer 可用；

FreeSql/FreeSql.xml

@@ -910,6 +910,15 @@
             </summary>
             <returns></returns>
         </member>
+        <member name="M:FreeSql.IInsert`1.ToDataTable">
+            <summary>
+            返回 DataTable 以便做 BulkCopy 数据做准备<para></para>
+            此方法会处理：<para></para>
+            类型、表名、字段名映射<para></para>
+            IgnoreColumns、InsertColumns
+            </summary>
+            <returns></returns>
+        </member>
         <member name="F:FreeSql.FieldAliasOptions.AsIndex">
             <summary>
             自动产生 as1, as2, as3 .... 字段别名<para></para>

FreeSql/Internal/CommonProvider/InsertProvider.cs

@@ -1,4 +1,5 @@
 using FreeSql.Internal.Model;
+using FreeSql.Extensions.EntityUtil;
 using SafeObjectPool;
 using System;
 using System.Collections.Generic;
@@ -136,8 +137,20 @@ namespace FreeSql.Internal.CommonProvider
             foreach (var col in table.Columns.Values)
             {
                 object val = col.GetMapValue(data);
-                if (col.Attribute.IsPrimary && col.Attribute.MapType.NullableTypeOrThis() == typeof(Guid) && (val == null || (Guid)val == Guid.Empty))
-                    col.SetMapValue(data, val = FreeUtil.NewMongodbId());
+                if (col.Attribute.IsPrimary)
+                {
+                    if (col.Attribute.MapType.NullableTypeOrThis() == typeof(Guid) && (val == null || (Guid)val == Guid.Empty))
+                        col.SetMapValue(data, val = FreeUtil.NewMongodbId());
+                    else if (col.CsType.NullableTypeOrThis() == typeof(Guid))
+                    {
+                        var guidVal = orm.GetEntityValueWithPropertyName(table.Type, data, col.CsName);
+                        if (guidVal == null || (Guid)guidVal == Guid.Empty)
+                        {
+                            orm.SetEntityValueWithPropertyName(table.Type, data, col.CsName, FreeUtil.NewMongodbId());
+                            val = col.GetMapValue(data);
+                        }
+                    }
+                }
                 if (orm.Aop.AuditValue != null)
                 {
                     var auditArgs = new Aop.AuditValueEventArgs(Aop.AuditValueType.Insert, col, table.Properties[col.CsName], val);