Ron Goral wrote:
>
> From: Rob Dixon [mailto:[EMAIL PROTECTED]
> Sent: Saturday, January 03, 2004 9:51 AM
> To: [EMAIL PROTECTED]
> Subject: Re: fetchall_hashref error: invalid number of parameters?
> >
> >
> > Ron Goral wrote:
> > >
> > > I am trying to hit a MySQL database using DBI::mysql. I am trying to get
> > > table information using the SQL - "SHOW TABLE STATUS".
> > >
> > > The statement handle prepares and then executes as it should, but when I
> > try
> > > to get the info via $sth->fetchall_hashref, I get the following error:
> > >
> > > =================================================
> > > DBI fetchall_hashref: invalid number of parameters: handle + 0 Usage:
> > > $h->fetchall_hashref()
> > > =================================================
> > >
> > > I'm not sure what form the data will be in when this statement is
> > executed,
> > > but the hashref is a hopeful thing.
> > >
> > > Here is the code after a good connection to the database -
> > >
> > > =================================================
> > > eval{$sth = $dbh->prepare("SHOW TABLE STATUS");};
> > > print qq[Error - $@ <br />] if $@; # No error here
> > >
> > > eval{$sth->execute();};
> > > print qq[Error - $@ <br />] if $@; # No error here
> > >
> > > my $ar_TableInfo;
> > > eval{$ar_TableInfo = $sth->fetchall_hashref;};
> > > print qq[Error - $@ <br />] if $@; # Error occurs here
> > >
> > > print qq[About to iterate the array of hashrefs.....<br />];
> > > foreach my $hr_TableInfo (@$ar_TableInfo)
> >
> > You're getting confused here. $ar_TableInfo is a hashref
> > so you can't dereference it as an array.
> >
> > > {
> > > foreach my $key (keys %{$hr_TableInfo})
> > > {print qq[$key is $hr_TableInfo->{$key}<br />];}
> > > }
> > > =================================================
> >
> > Like it says, you've supplied the wrong number of parameters
> > to the fetchall_hashref method. You need to pass a single
> > parameter saying which of the columns you want to use as the
> > keys of the returned hash. In this case it makes little sense
> > to use anything but the 'Name' column of the results, so you
> > could write something like:
> >
> > my $hr_TableInfo = $sth->fetchall_hashref('Name');
> >
> > foreach my $name (keys %{$hr_TableInfo}) {
> > my $rows = $hr_TableInfo->{$name}{Rows};
> > my $update_time = $hr_TableInfo->{$name}{Update_time};
> > }
> >
> > depending on what information you need from the results.
>
> fetchall_hashref is an array ref of hash refs (one hash ref per row
> contained in an array ref), so I have to dereference and iterate the array
> ref to get to the hash refs underneath. The DBI Manpage says:
>
> "It returns a reference to an array that contains one hash of field name and
> value pairs per row."
>
> Specifying column names is, unfortunately, an optional parameter for
> fetchall_arrayref not fetchall_hashref. =(
Hi Ron.
There's something odd somewhere. This is straight from
perldoc DBI
"fetchall_hashref"
$hash_ref = $sth->fetchall_hashref($key_field);
The "fetchall_hashref" method can be used to fetch all the data to
be returned from a prepared and executed statement handle. It
returns a reference to a hash that contains, at most, one entry per
row.
Try running:
use DBI;
print $DBI::VERSION, "\n";
I'm running DBI version 1.37 (But the POD in the DBI.pm source file claims
that it's for version 1.34!!)
I can't really help any further :-/
Rob
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