I've no idea what kind of "qry" you're talking about. But let's assume you want a database query where the contents of the where clause are controlled by the existance of data items that are stored in a hash. The keys of the hash are the column names and the values are the values that are required.

In the past I've used code something like this:

my $sql = 'select col_x, col_x from a_table';

# You'll be setting this hash up from some kind of
# input to your program. I'm using variables for
# illustrative purposes.
my %cols = (
  col_x => $foo,
  col_y => $bar,
  col_z => $baz,
);

my @where;
my @vals;
foreach (keys $cols) {
  if (defined $cols{$_}) {
    push @where, "$_ = ?";
    push @vals, $cols{$_};
  }
}

if (@where) {
  $sql .= ' where ' . join(' and ', @where);
}

my $sth = $dbh->prepare($sql);
$sth->execute(@vals);

[download]

Update: Or use SQL::Abstract as Corion points out.

--

<http://dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg

In reply to Re^2: A Case with 5 Var's by davorg
in thread A Case with 5 Var's by ultibuzz

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