G'day justsomeguy,

Here's some skeleton code that offers a general approach you could take. Also, given your request is a little on the vague side, I've provided a few alternative paths you may like to investigate.

Put your utilities in a module. I've used an OO module; a functional module may better suit your needs. I've shown hand-crafted constructor and accessor methods for demonstration purposes; you may prefer Moose (or similar). Also, I've used DBI (as indicated in your OP); other modules (e.g. DBIx::Class) may be a better choice for you.

package Your::SQL::Utils;

use DBI;
use DBD::Pg;

sub new {
    my ($class, ...) = @_;
    bless { dbh =>  _connect() } => $class;
}

sub _connect {
    ...
    return $dbh;
}

sub dbh { 
    my ($self) = @_;
    $self->{dbh};
}

sub some_query {
    my ($self, ...) = @_;

    ...
    my $sth = $self->dbh->prepare(...);
    ...
    $sth->execute(...);
    ...
}

sub other_query { ... }
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Your script might look something like this. (Here's the Getopt::Long documentation in case you're unfamiliar with this core module.)

# your_prog.pl

use Your::SQL::Utils;
use Getopt::Long;

my $query;
GetOptions('query=s' => \$query) or die "...";

my $util = Your::SQL::Utils::->new();
$util->$query();
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Serving suggestion:

$ your_prog.pl -q some_query
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