---
name: "RoPkg::DBCollection"
section: "3pm"
platform: "linux"
package: "libropkg-perl"
version: "0.4-1.3"
release: "Debian 11 (Bullseye)"
platforms: ["linux"]
url: "https://new.carta.tech/RoPkg::DBCollection"
---

# RoPkg::DBCollection(3pm)

base class who can be used for collections of database objects

## NAME

RoPkg::DBCollection - base class who can be used for collections of database objects

## VERSION

0\.1.3

## DESCRIPTION

RoPkg::DBCollection is a class who can be used as a base class for database collection of objects. Is used by *RoPkg::Simba::Mirrors* ,*RoPkg::Simba::Commands* and *RoPkg::Simba::Excludes*. This class should not be used directly in applications but derived.

## SUBROUTINES/METHODS

### new()

The class constructor. Accepts a hash with parameters. The parameters who can be passed to **new()** are:

- dbo - database object (instance of RoPkg::DB)

  - dbo\_method - database method (for use with RoPkg::DB)

  - table - the sql table name where the objects data can be found

  If you don't specify the **dbo** and **dbo\_method** parameters, a *Param::Missing* exception is raised.

### dbh()

returns the database handler (DBI object) used by the class.

### \_count($fields)

Returns the number of records who match the fields specified in `$fields`. This method should be overriden by the child classes. The `$fields` must me specified in SQL::Abstract format. Please refer to the SQL::Abstract documentation for more details about `$fields` format.

### \_get($class\_name, $fields, $order\_by)

Returns a array of initialized objects. The values are read from the database. `$class_name` is the name of the class who's gonna be instanciated. When creating the class instance dbo and dbo\_method parameters are passed to the **new()** method. The records from the database must match the `$fields` parameter and the order is given by `$order_by`. For more details of these 2 parameters please refer to SQL::Abstract documentation.\
  Exceptions throwed:

- **Param::Missing** - when $class\_name has not been specified

  - **Param::Wrong** - when $class\_name is not a class name

  - **DB::NoResults** - when the query returned 0 results

  ## SYNOPSIS

```
 package RoPkg::Tester;

 use strict;
 use warnings;

 use Scalar::Util qw(blessed);
 use RoPkg::Exceptions;
 use RoPkg::DBCollection;
 use vars qw(@ISA);
 @ISA=qw(RoPkg::DBCollection);
 sub new {
   my ($class, %opt) = @_;
   my $self;

   $self = $class->SUPER::new(%opt);
   $self->{table} = 'Mirrors';

   return $self;
 }

 sub Count {
   my ($self) = @_;

   if (!blessed($self)) {
     OutsideClass->throw(
       error    => 'Called outside class instance',
       pkg_name => 'RoPkg::Tester',
     );
   }

   return $self->_count();
 }

 sub Get {
   my ($self, $fields) = @_;

   if (!blessed($self)) {
     OutsideClass->throw(
       error    => 'Called outside class instance',
       pkg_name => 'RoPkg::Tester'
     );
   }

   return $self->_get('RoPkg::Simba::Mirror');
 }
 1;
 sub main {
   my ($dbc, $dbp);

   $dbp = new RoPkg::DB();
   $dbp->Add(
           'dbi:mysql:database=mirrors_db;host=localhost',
           'root',
           '',
           'mirrors'
         );

   $dbc = new RoPkg::Tester(
            dbo => $dbp,
            dbo_method => 'db_mirrors'
          );

   print $dbc->Count(),$/;

   my @mirrors = $dbc->Get();
 }

 main();
```

## DIAGNOSTICS

This module comes with tests. To run them, unpack the source and use 'make test' command.

## PERL CRITIC

This modules is perlcritic level 2 compliant (with 1 exception)

## CONFIGURATION AND ENVIRONMENT

This module does not use any configuration files or environment variables. However, it is possible that some dependencies to do so. Please read the man page of each dependency to find out more information.

## DEPENDENCIES

This module use the following modules:

- \*) SQL::Abstract

  - \*) DBI

  - \*) Scalar::Util

  - \*) RoPkg

  ## INCOMPATIBILITIES

None known to the author

## BUGS AND LIMITATIONS

None known to the author

## SEE ALSO

RoPkg::Exceptions RoPkg::DB RoPkg::DBObject RoPkg::Simba::Mirrors

## AUTHOR

Subredu Manuel \<diablo@iasi.roedu.net\>

## LICENSE AND COPYRIGHT

Copyright (C) 2006 Subredu Manuel.  All Rights Reserved. This module is free software; you can redistribute it  and/or modify it under the same terms as Perl itself. The LICENSE file contains the full text of the license.