How can I fetch a single count value from a database with DBI?

database perl dbi
szabgab picture szabgab · Nov 1, 2009 · Viewed 29.1k times · Source

The following code seems to be just too much, for getting a single count value. Is there a better, recommended way to fetch a single COUNT value using plain DBI?

sub get_count {
   my $sth = $dbh->prepare("SELECT COUNT(*) FROM table WHERE...");
   $sth->execute( @params );
   my $($count) = $sth->fetchrow_array;
   $sth->finish;

   return $count;
}

This is shorter, but I still have two statements.

sub get_count_2 {
   my $ar = $dbh->selectall_arrayref("SELECT ...", undef, @params)
   return $ar->[0][0];
}

Answer

Dave Sherohman picture Dave Sherohman · Nov 1, 2009

Easy enough to do in one line with no extra variables:

$count = $dbh->selectrow_array('SELECT count(*) FROM table WHERE...', undef, @params);

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