删除Access数据库中重复的数据,只保留一条记录

1.将过滤的结果导入到临时表
select distinct * into 临时表 from 原表名
2.删除原表
delete table 原表名
3.将临时表的数据转移到原始表里
select distinct * into 原表名 from 临时表
4.删除临时表
drop table Tmp

 

       /// <summary>
        /// 删除重复数据，只保留一条数据 
        /// </summary>
        /// <param name="mdbPath">mdb路径</param>
        public void DistinctTable(string mdbPath)
        {
            try
            {
                string connectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data source=" + mdbPath;
                DataTable dtTableName = OleDbHelper.GetExcelTables(connectionString);
                AccessHelper acchelp = new AccessHelper(connectionString);
                for (int i = 0; i < dtTableName.Rows.Count; i++)
                {
                    string name = dtTableName.Rows[i]["TABLE_NAME"].ToString();
                    //1.将过滤的重复数据 存放在临时表里
                    acchelp.ExecuteSQL(@"select distinct * into tmpTable from " + name);
                    //2.删除原表
                    acchelp.ExecuteSQL(@"drop table " + name);
                    //3.将临时表的数据转移到原始表里
                    acchelp.ExecuteSQL(string.Format(@"select * into {0} from tmpTable", name));
                    //4.删除临时表
                    acchelp.ExecuteSQL(@"drop table tmpTable");

                }
                dtTableName.Clear(); dtTableName = null;
            }
            catch (Exception ex)
            {
               MessageBox.Show(ex.Message);
            }
        }