sybperl-l Archive

From: Michael Peppler <mpeppler at MBAY dot NET>
Subject: Re: any way to get the # of columns returned
Date: Nov 3 1997 4:48PM

Raja Sambamurty wrote:
> 
> Hi,
> 
> Using sybperl, I very often do the following
> 
> @retarr = $dbfh->sql ("select * from table");
> 
> Now I can do a print $#retarr to find out the number of rows returned,
> but what I need to know is the number of columns. The reason I need to
> know this is to do a print stmt as in
> 
> print "$retarr[0][1]\n";
>                ^^^^

You can use scalar(@{$retarr[0]}) to find out how many elements
are in the first row.

> 
> to determine how far to go with the subscripts. Is there a better way of
> doing this ? I guess I could always work around with a
> 
> foreach $i (0..$#retarr) {
>  my $j=0;
>  while ( defined $retarr[$i][$j] ) {
>     print "$retarr[$i][$j]";
>     $j++;
>  }
>  print "\n";
> }

That may bite you :-)

Remember that a Sybase NULL value is returned as the perl 'undef'
value, so if you have any NULL values in your result set the
while loop will end prematurely.

A better way to doe that would be something like

my ($i, $row);

foreach $row (@retarr) {
    for ($i = 0; $i < scalar(@$row); ++$i) {
         print "$$row[$i]";
    }
}

It's a lot easier to work with references than with multi-dimensional
arrays in certain situations....

Michael
-- 
Michael Peppler       -||-  Data Migrations Inc.
mpeppler@datamig.com  -||-  http://www.mbay.net/~mpeppler