C#实现oracle数据的查询和删除

C# code

public static void doInsertData()        {                      string conStr = "provider='OraOleDb.Oracle';Data Source=" +            "(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521)))" +            "(CONNECT_DATA =(SERVICE_NAME = test)));User Id=test;Password=test;";            string sqlInsertStr = "insert into SYM_SOFTWARE_COLLECTION" +             "(USERNAME,IP,MAC,YONGYOUSTATUS,YONGYOUEDITION,JINDIESTATUS,JINDIEEDITION,GUANJIAPOSTATUS,GUANJIAPOEDITION,RECORDTIME)" +                "values('" + username + "','" + ip + "','" + mac + "','" + yySta + "','" + yyEdition + "','" + jdSta + "','"                    + jdEdition + "','" + gjpSta + "','" + gjpEdition + "', sysdate )";            String sqlQueryStr = "select * from SYM_SOFTWARE_COLLECTION  where USERNAME='test3';";            String sqlDeleteStr = "delete from SYM_SOFTWARE_COLLECTION  where USERNAME='test2';";            OleDbConnection sqlCon = new OleDbConnection(conStr);            try            {                sqlCon.Open();                //执行插入没问题，执行查询和删除时都有报错了                //OleDbCommand cmd = new OleDbCommand(sqlInsertStr, sqlCon);                //OleDbCommand cmd = new OleDbCommand(sqlDeleteStr, sqlCon);                OleDbCommand cmd = new OleDbCommand(sqlQueryStr, sqlCon);                                cmd.ExecuteNonQuery();            }            catch (Exception ex)            {                Console.WriteLine(ex.Message);            }            finally            {                sqlCon.Close();            }        }

执行查询和删除时都报错了：ORA-00911: invalid character
刚接触oracle
有点急，求有经验的高手帮忙解答一下，谢谢。。。。

[解决办法]
String sqlQueryStr = "select * from SYM_SOFTWARE_COLLECTION where USERNAME='test3';";
String sqlDeleteStr = "delete from SYM_SOFTWARE_COLLECTION where USERNAME='test2';";
双引号里面还有分号。。