get undefined error when trying to invoke SQL query in perl script

Angharad has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks
What sorts of things would cause a

Can't call method "bind_param" on an undefined value at nameofscript.p
+l
[download]

I'm sure that I've initialised the relevant variable - its at the top of the script as

my $variable = " ";
[download]

and then later is assigned a proper value. I even print out the variable to check it has a value in it before invoking the SQL query that uses the variable.
Any useful tips/ suggestions as to what I should look for?

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Re: get undefined error when trying to invoke SQL query in perl script by derby (Abbot) on Oct 04, 2006 at 14:04 UTC
Need more code. The problem isn't with the variable you're trying to bind but the variable invoking the bind_param call. The normal sequence of events is something like this: `my $dbh = ....; my $sth = $dbh->prepare( "SELECT fld from tab where fld = ?" ); $sth->bind_param(1, "val"); $sth->execute;` [download] So from your error message above, I would assume your statement handle is bad. -derby	[reply] [d/l]
Re: get undefined error when trying to invoke SQL query in perl script by shmem (Chancellor) on Oct 04, 2006 at 14:05 UTC
Look for a line reading like `$variable->bind_param()` [download] in your code. `$variable` seems to be undefined. If you had provided your script, I could be more precise. See How (Not) To Ask A Question. --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l] [select]