It's a simple case of re-factoring to strip out this redundancy. Make a simple template function first:
sub getById
{
my ($table, $column, $id) = @_;
my $dbh = sqlConnect();
my $sth = $dbh->prepare("SELECT * FROM $table WHERE $column=?");
$sth->execute($id);
my $result = $sth->fetchrow_hashref();
$sth->finish();
return $result;
}
Now you can call this function with the appropriate parameters, or, try and make these wrapper functions:
sub getCustomerById
{
my ($id) = @_;
return getById("customers", "cust_id", $id);
}
This can be tuned to match any of your various "getXById" functions by simply supplying different parameters.