...
my $col_spec = my $val_spec = "(";
for my $column ( keys %data )
{
   $col_spec .= "$column,";
   $val_spec .= "$data{$column},";
}
$col_spec =~ s/,$/\)/;
$val_spec =~ s/,$/\)/;

my $sql = "insert into my_table $col_spec values $val_spec";

##</code><code>##

my $col_spec = join( ",", sort keys %data );
my $val_spec = join( ",", map { $data{$_} } sort keys %data );
my $sql = "insert into my_table ($col_spec) values ($val_spec)";