(1) should not be valid either. first_name is not part of your select
statement. So, how would you be able to order your result set with it?
I think what Hytham wants to do here is dynamically build an SQL
statement. Your SQL string should be built before you try to prepare it.
-Ian
Paul DuBois wrote:
> At 18:05 +0300 6/10/02, Hytham Shehab wrote:
>
>> hi all of u,
>> i got a simple question, why (1) is valid, however, (2) is not ?!!
>> (1) sorting order is explicity typed in the query statement:
>> $sth = $dbh->prepare("select student_name from students order by
>> first_name
>> asc");
>> $sth->execute();
>> (2) sorting order is passed as a bind parameter:
>> $sort = 'asc';
>> $sth = $dbh->prepare("select student_name from students order by
>> first_name
>> ?");
>> $sth->execute($sort);
>
>
> Because placeholders are valid only for data values, not for keywords
> or identifiers.
>
>> thx v. much
>> --
>> Hytham Shehab
>
>
