On Tue, Apr 29, 2008 at 09:29:43AM +0100, Martin Evans wrote:
>
> Looking at this again I don't think DBD::ODBC will do as you expect. I'm
> guessing you are doing something like:
>
> $sth = $dbh->prepare(
> 'insert into x (a,b,c,d,e,f) values(:1,:2,:3,:3,:4,:4)');
> $sth->execute('p','q','r','s');
>
> I cannot see in the DBI pod anything which says this should work.
Drivers that support named placeholders (":foo") should allow :foo to
appear in a statement more than once. The value would be bound using:
$sth->bind_param( ":foo", $value )
and the execute() method should be called with no arguments.
Drivers that only support un-named placeholders ("?") obviously can't
distinguish one placeholder from another other than by their index
(sequence) number: 1, 2, 3 etc. For these placeholders values can be
bound using:
$sth->bind_param( $index, $value )
where $index is a simple integer with no colon, or by passing values to
the execute() method call.
Drivers that support named placeholders like ":N" where N is an integer,
could support both forms of binding: bind_param(":1",$v) and execute($v)
It's not dis-allowed. Driver docs should clarify this issue.
The DBI docs just says "their use is not portable" about all forms of
named placeholders. Not very useful I guess :)
> If you change the execute to:
>
> $sth->execute('p','q','r','r','s','s')
>
> it should work
Er, I don't think it should. That would only work if the driver was
treating ":N" style placeholders as "?" style placeholders, which would
be a bug anyway.
If the driver is capable of mapping execute() arguments to ":N" style
placeholders then the original code should work.
If it's not then a useful error message should be generated.
> but I'd change your SQL to use ? for parameters anyway as
> it is more portable and quicker in DBD::ODBC. Perhaps if Tim is reading
> this he could clarify whether it was ever his intention that the example
> above should work?
I'll add a note to the docs (hopefully) clarifying the issue.
Tim.
