diff --git a/Src/Asp.NetCore2/OscarTest/Config.cs b/Src/Asp.NetCore2/OscarTest/Config.cs
index 5b7feef47..c767f27a5 100644
--- a/Src/Asp.NetCore2/OscarTest/Config.cs
+++ b/Src/Asp.NetCore2/OscarTest/Config.cs
@@ -15,16 +15,16 @@ namespace OrmTest
         /// Account have permission to create database
         /// 用有建库权限的数据库账号
         /// </summary>
-        public static string ConnectionString = "PORT=2003;DATABASE=osrdb;HOST=localhost;PASSWORD=szoscar55;USER ID=SYSDBA";
+        public static string ConnectionString = "PORT=2003;DATABASE=osrdb;HOST=101.34.16.141;PASSWORD=szoscar555;USER ID=SYSDBA;";
         /// <summary>
         /// Account have permission to create database
         /// 用有建库权限的数据库账号
         /// </summary>
-        public static string ConnectionString2 = "PORT=2003;DATABASE=osrdb;HOST=localhost;PASSWORD=szoscar55;USER ID=SYSDBA";
+        public static string ConnectionString2 = "PORT=2003;DATABASE=osrdb;HOST=101.34.16.141;PASSWORD=szoscar555;USER ID=SYSDBA;";
         /// <summary>
         /// Account have permission to create database
         /// 用有建库权限的数据库账号
         /// </summary>
-        public static string ConnectionString3 = "PORT=2003;DATABASE=osrdb;HOST=localhost;PASSWORD=szoscar55;USER ID=SYSDBA";
+        public static string ConnectionString3 = "PORT=2003;DATABASE=osrdb;HOST=101.34.16.141;PASSWORD=szoscar555;USER ID=SYSDBA;";
     }
 }
diff --git a/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/CodeFirst/OscarCodeFirst.cs b/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/CodeFirst/OscarCodeFirst.cs
index 5cb51c4cc..5474027d2 100644
--- a/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/CodeFirst/OscarCodeFirst.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/CodeFirst/OscarCodeFirst.cs
@@ -67,11 +67,11 @@ namespace SqlSugar
 
         protected override void ChangeKey(EntityInfo entityInfo, string tableName, EntityColumnInfo item)
         {
-            this.Context.DbMaintenance.UpdateColumn(tableName, EntityColumnToDbColumn(entityInfo, tableName, item));
-            if (!item.IsPrimarykey)
-                this.Context.DbMaintenance.DropConstraint(tableName,null);
-            if (item.IsPrimarykey)
-                this.Context.DbMaintenance.AddPrimaryKey(tableName, item.DbColumnName);
+            //this.Context.DbMaintenance.UpdateColumn(tableName, EntityColumnToDbColumn(entityInfo, tableName, item));
+            //if (!item.IsPrimarykey)
+            //    this.Context.DbMaintenance.DropConstraint(tableName,null);
+            //if (item.IsPrimarykey)
+            //    this.Context.DbMaintenance.AddPrimaryKey(tableName, item.DbColumnName);
         }
 
     }
diff --git a/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/DbMaintenance/OscarDbMaintenance.cs b/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/DbMaintenance/OscarDbMaintenance.cs
index 3b0e08f16..a0d59ec0a 100644
--- a/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/DbMaintenance/OscarDbMaintenance.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Realization/Oscar/DbMaintenance/OscarDbMaintenance.cs
@@ -244,15 +244,36 @@ INFO_SCHEM.ALL_TAB_COLUMNS WHERE upper(TABLE_NAME)=upper('{0}')
         #region Methods
         public override bool UpdateColumn(string tableName, DbColumnInfo columnInfo)
         {
+
             tableName = this.SqlBuilder.GetTranslationTableName(tableName);
             var columnName= this.SqlBuilder.GetTranslationColumnName(columnInfo.DbColumnName);
-            string sql = GetUpdateColumnSql(tableName, columnInfo);
-            this.Context.Ado.ExecuteCommand(sql);
+            string type = GetType(tableName, columnInfo);
+            //this.Context.Ado.ExecuteCommand(sql);
+
+            string sql= @"ALTER TABLE {table} ALTER TYPE {column} {type};ALTER TABLE {table} ALTER COLUMN {column} {null}";
+
             var isnull = columnInfo.IsNullable?" DROP NOT NULL ": " SET NOT NULL ";
-            this.Context.Ado.ExecuteCommand(string.Format("alter table {0} alter {1} {2}",tableName,columnName, isnull));
+
+            sql = sql.Replace("{table}", tableName)
+                .Replace("{type}", type)
+                .Replace("{column}", columnName)
+                .Replace("{null}", isnull); 
+            this.Context.Ado.ExecuteCommand(sql);
             return true;
         }
 
+        protected string GetType(string tableName, DbColumnInfo columnInfo)
+        {
+            string columnName = this.SqlBuilder.GetTranslationColumnName(columnInfo.DbColumnName);
+            tableName = this.SqlBuilder.GetTranslationTableName(tableName);
+            string dataSize = GetSize(columnInfo);
+            string dataType = columnInfo.DataType;
+            //if (!string.IsNullOrEmpty(dataType))
+            //{
+            //    dataType =  dataType;
+            //}
+            return dataType +""+ dataSize;
+        }
         protected override string GetUpdateColumnSql(string tableName, DbColumnInfo columnInfo)
         {
             string columnName = this.SqlBuilder.GetTranslationColumnName(columnInfo.DbColumnName);
@@ -371,6 +392,13 @@ INFO_SCHEM.ALL_TAB_COLUMNS WHERE upper(TABLE_NAME)=upper('{0}')
         public override List<DbColumnInfo> GetColumnInfosByTableName(string tableName, bool isCache = true)
         {
             var result= base.GetColumnInfosByTableName(tableName.TrimStart('"').TrimEnd('"'), isCache);
+            foreach (var columnInfo in result) 
+            {
+                if (columnInfo.IsIdentity && !columnInfo.DataType.ObjToString().ToLower().Contains("int")) 
+                {
+                    columnInfo.IsIdentity = false;
+                }
+            }
             string sql = "select * from " + SqlBuilder.GetTranslationTableName(tableName) + " WHERE 1=2 ";
             var oldIsEnableLog = this.Context.Ado.IsEnableLogEvent;
             this.Context.Ado.IsEnableLogEvent = false;