update 执行了也没有报错，但修改内容没有成功

Question

strSql.Append("update HouseInfo set ");
  strSql.Append("hName=@hName");
  strSql.Append(" where houseId=@houseId ");
  OleDbParameter[] parameters = {
new OleDbParameter("@houseId", OleDbType.Integer,4),
new OleDbParameter("@hName", OleDbType.VarChar,50)};
  parameters[0].Value = model.houseId;
  parameters[1].Value = model.hName;
  try
  {
  int rows = OleDbHelper.ExecuteNonQuery(strSql.ToString(), parameters);
  result = true;
  }
  catch (Exception ex)
  {
  throw ex;
  }
执行完后，没有报错，但rows是0，不知道是什么原因。
SELECT * FROM [HouseInfo] where houseId=1执行也有数据

Answer 1

OleDbHelper.ExecuteNonQuery 这个方法是怎么实现的啊

Answer 2

/// <summary>
        /// 执行SQL语句，返回影响的记录数
        /// </summary>
        /// <param name="SQLString">SQL语句</param>
        /// <returns>影响的记录数</returns>
        public static int ExecuteNonQuery(string SQLString, params OleDbParameter[] cmdParms)
        {
            using (OleDbConnection connection = new OleDbConnection(GetSqlConnection()))
            {
                using (OleDbCommand cmd = new OleDbCommand())
                {
                    try
                    {
                        PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                        int rows = cmd.ExecuteNonQuery();
                        cmd.Parameters.Clear();
                        return rows;
                    }
                    catch (System.Data.OleDb.OleDbException E)
                    {
                        throw new Exception(E.Message);
                    }
                }
            }
        }        /// <summary>
        /// 
        /// </summary>
        /// <param name="cmd"></param>
        /// <param name="conn"></param>
        /// <param name="trans"></param>
        /// <param name="cmdText"></param>
        /// <param name="cmdParms"></param>
        private static void PrepareCommand(OleDbCommand cmd, OleDbConnection conn, OleDbTransaction trans, string cmdText, OleDbParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (trans != null)
                cmd.Transaction = trans;
            cmd.CommandType = CommandType.Text;//cmdType;
            if (cmdParms != null)
            {
                foreach (OleDbParameter parm in cmdParms)
                    cmd.Parameters.Add(parm);
            }
        }

Answer 3

注意参数顺序
参考：http://hi.baidu.com/jelinux/blog/item/e2efb918d3ba7d0b34fa410d.html

Answer 4

parameters  参数位置调下 跟sql语句中对应
houseId放后 hName放前

Answer 5

obledbparameter参数要一致
new OleDbParameter("@hName", OleDbType.VarChar,50)，
new OleDbParameter("@houseId", OleDbType.Integer,4)

Answer 6

参看我之前的一个帖子。http://topic.csdn.net/u/20100810/14/2273c1f1-631c-4b5d-8d71-8206a32dfe1d.html