string sql = "select count(1) from T_USERINFO wheres_userid=:userid ands_userpassword=:password";
OracleParameter p1 =new OracleParameter(":userid", OracleType.VarChar,20);
OracleParameter p2 =new OracleParameter(":password", OracleType.VarChar ,20);
p1.Value = userid;
p2.Value = password;
OracleParameter[] op ={p1,p2};
return DbHelperOra.GetSingle(sql,op);
}