string ConnStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= taizhang.mdb";

OleDbConnection myConn = new OleDbConnection(ConnStr);
myConn.Open();
String sqlcmd = "Insert into table() values();
OleDbCommand Cmd = new OleDbCommand(sqlcmd, myConn);
Cmd.ExecuteNonQuery();
myConn.Close();

此段代码能新增一条记录,并且我也能查询到该条记录,但是我关闭系统,重新打开,就查询不到这条记录,高手请指教????