fetching rows problem

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

$st = $db->prepare( "SELECT count(*) FROM members WHERE user=?" );
  $st->execute($user);
  $rows = $st->fetchrow_array();

  if ($rows)
   {
      print font( {-size=>5, -color=>'Lime'}, "Το όνομα Χρήστη είναι π
+ιασμένο! Παρακαλώ διάλεξε ένα άλλο!" );
      exit 0;
   }
[download]

i try the above to check if there are any records returned but it fails. any idea why?
and also

 $st = $db->prepare( "SELECT count(*) FROM members" );
   $st->execute();
   $row = $st->fetchrow_hashref;
print $row->{'count(*)}
[download]

i am trying the above to get the total number of rows returned from the sql statement but it aint working why?

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Re: fetching rows problem by b10m (Vicar) on Feb 25, 2004 at 21:32 UTC
The first piece of code seems "valid" to me. Could you specify what exactly fails? As for the second snippet, you have a typo in there (`print $row->{'count()}` you forget an apostrophe (') ). I would write it something like this (to make it more readable): `$st = $db->prepare("SELECT count() AS total FROM members"); $st->execute(); my $row = $st->fetchrow_hashref(); print $row->{total}."\n";` [download] Update: You can use your approach, but don't forget the apostrophe (single quote): `print $row->{'count(*)'}."\n";` [download] -- b10m All code is usually tested, but rarely trusted.	[reply] [d/l] [select]
Re: fetching rows problem by matija (Priest) on Feb 25, 2004 at 21:24 UTC
Instead of `$rows = $st->fetchrow_array();` You should do `($rows) = $st->fetchrow_array();` The reason for this is that you want the first element of the returned array in your `$row` - if you do it without the parens, you will get the number of elements in the array, which is not what you want. For your second problem, change your SQL to `SELECT count(*) as c FROM members`. Once you've done that, you can reference the value as `$$row{c}`.	[reply] [d/l] [select]
Re: Re: fetching rows problem by cchampion (Curate) on Feb 25, 2004 at 23:50 UTC
if you do it without the parens, you will get the number of elements in the array, No. It doesn't work that way. fetchrow_array in scalar context will return the first or the last field (See DBI specification change). Which one is currently undefined, but with a query that returns only one value the issue is irrelevant.	[reply]