You might want to check out Ima::DBI.

It's a package for OO style handling of database connections and caching at the class level.

package My::Collection;

use base qw/Ima::DBI/;

__PACKAGE__->set_db('foo', "dbi:pg:foo", "user", "pass", {});
__PACKAGE__->set_db('bar', "dbi:pg:bar", "user", "pass", {});
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The connection is automatically made the first time you refer to the handle.

my $foo_dbh = My::Collection->db_foo;
my $bar_dbh = My::Collection->db_bar;
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