添加一行数据，insertinto 语法错误

string connstr = "Provider=Microsoft.Jet.OleDb.4.0;";
connstr += @"Data Source=D:\Merger201503016caohuan\GEARCNC.mdb";//创建连接对象

        OleDbConnection tempconn = new OleDbConnection(connstr);

        OleDbDataAdapter WorkPieceDataDA = new OleDbDataAdapter("select * from WorkPieceData", tempconn);

        OleDbCommandBuilder builder = new OleDbCommandBuilder(WorkPieceDataDA);
        DataSet ds = new DataSet();
        WorkPieceDataDA.Fill(ds, "WorkPieceData");

        //新建一行
        DataRow dr = ds.Tables["WorkPieceData"].NewRow(); 

        //为各字段赋值
        dr["齿数"]=ChiShu.Text;
        dr["法面模数"] = BiaoZhunMoShu.Text;

        ds.Tables["WorkPieceData"].Rows.Add(dr);
       // OleDbCommandBuilder builder = new OleDbCommandBuilder(WorkPieceDataDA);

        WorkPieceDataDA.Update(ds, "WorkPieceData");//报错insert into语句错误

tempconn 没打开啊