Difference between revisions of "API:EPrints/DataSet"

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<!-- Pod2Wiki=_preamble_  
 
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This page has been automatically generated from the EPrints 3.2 source. Any wiki changes made between the 'Pod2Wiki=*' and 'Edit below this comment' comments will be lost.
 
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  -->{{API}}{{Pod2Wiki}}{{API:Source|file=EPrints/DataSet.pm|package_name=EPrints::DataSet}}[[Category:API|DATASET]][[Category:API:EPrints/DataSet|DATASET]]<div><!-- Edit below this comment -->
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  -->{{API}}{{Pod2Wiki}}{{API:Source|file=perl_lib/EPrints/DataSet.pm|package_name=EPrints::DataSet}}[[Category:API|DATASET]][[Category:API:EPrints/DataSet|DATASET]]<div><!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki=_private_ --><!-- Pod2Wiki=head_name -->
 
<!-- Pod2Wiki=_private_ --><!-- Pod2Wiki=head_name -->
 
==NAME==
 
==NAME==
'''EPrints::DataSet''' - a dataset is a set of records in the eprints system with the same metadata.
+
'''EPrints::DataSet''' - a set of records with the same metadata scheme
  
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<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
 
 
<!-- Pod2Wiki=head_synopsis -->
 
<!-- Pod2Wiki=head_synopsis -->
 
==SYNOPSIS==
 
==SYNOPSIS==
  my $dataset = $repository-&gt;get_dataset( "inbox" );
+
<source lang="perl">my $dataset = $repository->dataset( "inbox" );
 
+
 
  print sprintf("There are %d records in the inbox\n",
+
print sprintf("There are %d records in the inbox\n",
    $dataset-&gt;count);
+
$dataset->count);
 
+
 
  $string = $dataset-&gt;base_id; # eprint
+
$string = $dataset->base_id; # eprint
  $string = $dataset-&gt;id; # inbox
+
$string = $dataset->id; # inbox
 
+
 
  $dataobj = $dataset-&gt;create_dataobj( $data );
+
$dataobj = $dataset->create_dataobj( $data );
  $user = $dataset-&gt;dataobj( 23 );
+
$user = $dataset->dataobj( 23 );
 
+
 
  $search = $dataset-&gt;prepare_search( %options );
+
$search = $dataset->prepare_search( %options );
  $list = $dataset-&gt;search( %options ); # prepare_search( %options )-&gt;execute
+
$list = $dataset->search( %options ); # prepare_search( %options )->execute
  $list = $dataset-&gt;search; # match ALL
+
$list = $dataset->search; # match ALL
 
+
 
  $metafield = $dataset-&gt;field( $fieldname );
+
$metafield = $dataset->field( $fieldname );
  $metafield = $dataset-&gt;key_field;
+
$metafield = $dataset->key_field;
  @metafields = $dataset-&gt;fields;  
+
@metafields = $dataset->fields;
 
+
 
  $dataset-&gt;search-&gt;map( sub {}, $ctx );
+
$dataset->search->map( sub {}, $ctx );
  $n = $dataset-&gt;search-&gt;count;  
+
$n = $dataset->search->count;  
  $ids = $dataset-&gt;search-&gt;ids;
+
$ids = $dataset->search->ids;
  $list = $dataset-&gt;list( \@ids );
+
$list = $dataset->list( \@ids );</source>
 
+
 
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<!-- Edit below this comment -->
 
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</div>
 
 
<!-- Pod2Wiki=head_description -->
 
<!-- Pod2Wiki=head_description -->
 
==DESCRIPTION==
 
==DESCRIPTION==
This module describes an EPrint dataset.
+
This module describes a dataset.
  
A repository has several datasets that make up the repository's database. The list of dataset ids can be obtained from the repository object (see [[API:EPrints/Repository|EPrints::Repository]]).
+
A repository has several datasets that make up the repository's metadata schema. The list of dataset ids can be obtained from the repository object (see [[API:EPrints/Repository|EPrints::Repository]]).
  
A normal dataset (eg. "user") has a package associated with it  (eg. EPrints::DataObj::User) which must be a subclass of EPrints::DataObj  and a number of SQL tables which are prefixed with the dataset name. Most datasets also have a set of associated EPrints::MetaField's which may be optional or compulsary depending on the type eg. books have editors but posters don't but they are both EPrints.
+
A normal dataset (eg. "user") has a package associated with it  (eg. [[API:EPrints/DataObj/User|EPrints::DataObj::User]]) which must be a subclass of [[API:EPrints/DataObj|EPrints::DataObj]] and a number of SQL tables which are prefixed with the dataset name. Most datasets also have a set of associated [[API:EPrints/MetaField|EPrints::MetaField]]'s which may be optional or required depending on the type eg. books have editors but posters don't but they are both EPrints.
  
 
The fields contained in a dataset are defined by the data object and by any additional fields defined in cfg.d. Some datasets don't have any fields.
 
The fields contained in a dataset are defined by the data object and by any additional fields defined in cfg.d. Some datasets don't have any fields.
  
Some datasets are "virtual" datasets made from others. Examples include  "inbox", "archive", "buffer" and "retired" which are all virtual datasets  of of the "eprint" dataset. That is to say "inbox" is a subset of "eprint"  and by inference contains EPrints::DataObj::EPrints. You can define your  own virtual datasets which opperate on existing datasets.
+
Some datasets are "virtual" datasets made from others. Examples include  "inbox", "archive", "buffer" and "deletion" which are all virtual datasets  of of the "eprint" dataset. That is to say "inbox" is a subset of "eprint"  and by inference contains [[API:EPrints/DataObj/EPrint|EPrints::DataObj::EPrint]]. You can define your  own virtual datasets which opperate on existing datasets.
  
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<!-- Edit below this comment -->
 
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<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_creating_custom_datasets -->
<!-- Pod2Wiki=head_object_methods -->
+
==CREATING CUSTOM DATASETS==
===Object Methods===
+
New datasets can be defined in a configuration file, e.g.
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+
<!-- Edit below this comment -->
+
  
 +
<pre>  $c-&gt;{datasets}-&gt;{bread} = {
 +
    class =&gt; "EPrints::DataObj::Bread",
 +
    sqlname =&gt; "bread",
 +
  };</pre>
  
<!-- Pod2Wiki= -->
+
This defines a dataset with the id <code>bread</code> (must be unique). The dataobj package (class) to instantiate objects with is <code>EPrints::DataObj::Bread</code>, which must be a sub-class of [[API:EPrints/DataObj|EPrints::DataObj]]. Lastly, the database tables used by the dataset will be called 'bread' or prefixed 'bread_'.
</div>
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<!-- Pod2Wiki=item_base_id -->
+
====$id = $ds-&gt;base_id====
+
  
  $ds = $repo-&gt;dataset( "inbox" );
+
Other optional properties:
  $id = $ds-&gt;base_id; # returns "eprint"
+
 
+
Returns the identifier of the base dataset for this dataset (same as {{API:PodLink|file=|package_name=|section=id|text=/id}} unless this dataset is virtual).
+
  
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+
<pre> columns - an array ref of field ids to default the user view to
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+
  datestamp - field id to use to sort this dataset
<!-- Edit below this comment -->
+
  import - is the dataset importable?
 +
  index - is the dataset text-indexed?
 +
  order - is the dataset orderable?
 +
  virtual - completely virtual dataset (no database tables)</pre>
  
 +
To make one dataset a virtual dataset of another (as 'inbox' is to 'eprint') use the following properties:
  
<!-- Pod2Wiki= -->
+
<pre>  confid - the super-dataset this is a virtual sub-dataset of
</div>
+
  dataset_id_field - the field containing the sub-dataset id
<!-- Pod2Wiki=item_field -->
+
  filters - an array ref of filters to apply when retrieving records</pre>
====$metafield = $ds-&gt;field( $fieldname )====
+
  
Returns the [[API:EPrints/MetaField|EPrints::MetaField]] from this dataset with the given name, or undef.
+
As with system datasets, the [[API:EPrints/MetaField|EPrints::MetaField]]s can be defined via [[API:EPrints/DataObj#get_system_field_info|EPrints::DataObj/get_system_field_info]] or via configuration:
  
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+
<pre>  $c-&gt;add_dataset_field(
<span style='display:none'>User Comments</span>
+
    "bread",
<!-- Edit below this comment -->
+
    { name =&gt; "breadid", type =&gt; "counter", sql_counter =&gt; "bread" }
 +
  );
 +
  $c-&gt;add_dataset_field(
 +
    "bread",
 +
    { name =&gt; "toasted", type =&gt; "bool", }
 +
  );
 +
  $c-&gt;add_dataset_field(
 +
    "bread",
 +
    { name =&gt; "description", type =&gt; "text", }
 +
  );</pre>
  
 +
See [[API:EPrints/RepositoryConfig#add_dataset_field|EPrints::RepositoryConfig/add_dataset_field]] for details on <code>add_dataset_field</code>.
  
<!-- Pod2Wiki= -->
+
Creating a fully-operational dataset will require more configuration files. You will probably want at least a [[API:EPrints/Workflow|workflow]], [[API:EPrints/Citation|citations]] for the summary page, search results etc, and permissions and searching settings:
</div>
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<!-- Pod2Wiki=item_id -->
+
====$id = $ds-&gt;id====
+
  
Return the id of this dataset.
+
<pre>  push @{$c-&gt;{user_roles}-&gt;{admin}}, qw(
 +
    +bread/create
 +
    +bread/edit
 +
    +bread/view
 +
    +bread/destroy
 +
    +bread/details
 +
  );
 +
  push @{$c-&gt;{plugins}-&gt;{"Export::SummaryPage"}-&gt;{params}-&gt;{accept}}, qw(
 +
    dataobj/bread
 +
  );
 +
  $c-&gt;{datasets}-&gt;{bread}-&gt;{search}-&gt;{simple} = {
 +
    search_fields =&gt; {
 +
      id =&gt; "q",
 +
      meta_fields =&gt; [qw(
 +
        breadid
 +
        description
 +
      )],
 +
    },
 +
  };</pre>
  
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<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_methods -->
<!-- Pod2Wiki=item_count -->
+
==METHODS==
====$n = $ds-&gt;count( $session )====
+
<!-- Edit below this comment -->
  
Return the number of records in this dataset.
 
  
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<!-- Pod2Wiki=head_class_methods -->
 +
===Class Methods===
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_object_methods -->
<!-- Pod2Wiki=item_fields -->
+
===Object Methods===
====@fields = $ds-&gt;fields====
+
$id = $ds-&gt;base_id
 +
<pre>  $ds = $repo-&gt;dataset( "inbox" );
 +
  $id = $ds-&gt;base_id; # returns "eprint"</pre>
  
Returns a list of the [[API:EPrints/MetaField|EPrints::MetaField]]s belonging to this dataset.
+
Returns the identifier of the base dataset for this dataset (same as [[API:EPrints/DataSet#id|id]] unless this dataset is virtual).
  
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+
$metafield = $ds-&gt;field( $fieldname )
<span style='display:none'>User Comments</span>
+
Returns the [[API:EPrints/MetaField|EPrints::MetaField]] from this dataset with the given name, or undef.
<!-- Edit below this comment -->
+
  
 +
$id = $ds-&gt;id
 +
Return the id of this dataset.
  
<!-- Pod2Wiki= -->
+
$n = $ds-&gt;count( $session )
</div>
+
Return the number of records in this dataset.
<!-- Pod2Wiki=item_key_field -->
+
 
====$field = $ds-&gt;key_field====
+
@fields = $ds-&gt;fields
 +
Returns a list of the [[API:EPrints/MetaField|EPrints::MetaField]]s belonging to this dataset.
  
 +
$field = $ds-&gt;key_field
 
Return the [[API:EPrints/MetaField|EPrints::MetaField]] representing the primary key field.
 
Return the [[API:EPrints/MetaField|EPrints::MetaField]] representing the primary key field.
  
 
Always the first field.
 
Always the first field.
  
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+
  $dataobj = $ds-&gt;make_dataobj( $epdata )
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+
<!-- Edit below this comment -->
+
 
+
 
+
<!-- Pod2Wiki= -->
+
</div>
+
<!-- Pod2Wiki=item_make_dataobj -->
+
====$dataobj = $ds-&gt;make_dataobj( $epdata )====
+
 
+
 
Return an object of the class associated with this dataset, always a subclass of [[API:EPrints/DataObj|EPrints::DataObj]].
 
Return an object of the class associated with this dataset, always a subclass of [[API:EPrints/DataObj|EPrints::DataObj]].
  
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Returns $epdata if no class is associated with this dataset.
 
Returns $epdata if no class is associated with this dataset.
  
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+
$obj = $ds-&gt;create_dataobj( $data )
<span style='display:none'>User Comments</span>
+
Returns a new object in this dataset based on $data or undef on failure.
<!-- Edit below this comment -->
+
  
 +
If $data describes sub-objects then those will also be created.
  
<!-- Pod2Wiki= -->
+
$dataobj = $ds-&gt;dataobj( $id )
</div>
+
Returns the object from this dataset with the given id, or undefined.
<!-- Pod2Wiki=item_create_dataobj -->
+
====$obj = $ds-&gt;create_dataobj( $data )====
+
  
Returns a new object in this dataset based on $data or undef on failure.
+
$repository = $ds-&gt;repository
 +
Returns the [[API:EPrints/Repository|EPrints::Repository]] to which this dataset belongs.
  
If $data describes sub-objects then those will also be created.
+
$searchexp = $ds-&gt;prepare_search( %options )
 +
Returns a [[API:EPrints/Search|EPrints::Search]] for this dataset with %options.
  
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+
$list = $ds-&gt;search( %options )
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+
Short-cut to [[API:EPrints/DataSet#prepare_search|prepare_search]]( %options )-&gt;execute.
<!-- Edit below this comment -->
+
  
 +
* satisfy_all
 +
<pre>  satisfy_all"=&gt;1</pre>
  
<!-- Pod2Wiki= -->
+
: Satify all conditions specified. 0 means satisfy any of the conditions specified. Default is 1
</div>
+
<!-- Pod2Wiki=item_dataobj -->
+
====$dataobj = $ds-&gt;dataobj( $id )====
+
  
Returns the object from this dataset with the given id, or undefined.
+
* staff
 +
<pre>  "staff"=&gt;1</pre>
  
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+
: Do search as an adminstrator means you get everything back
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+
<!-- Edit below this comment -->
+
  
 +
* custom_order
 +
<pre>  "custom_order" =&gt; "field1/-field2/field3"</pre>
  
<!-- Pod2Wiki= -->
+
: Order the search results by field order. prefixing the field name with a "-" results in reverse ordering
</div>
+
<!-- Pod2Wiki=item_repository -->
+
====$repository = $ds-&gt;repository====
+
  
Returns the [[API:EPrints/Repository|EPrints::Repository]] to which this dataset belongs.
+
* filters
 +
<pre>  "filters" =&gt; \@(
 +
                        { meta_fields=&gt;[ "field1", "field2" "document.field3" ],
 +
                          merge=&gt;"ANY", match=&gt;"EX",
 +
                          value=&gt;"bees"
 +
                        },
 +
                        { meta_fields=&gt;[ "field4" ],
 +
                          value=&gt; qw( honey ),
 +
                          match=&gt;"IN"
 +
                        }
 +
                      );</pre>
 +
 
 +
: This searchs for 'bees' in <code>field1</code> or <code>field2</code> or <code>document.field3</code>, and 'honey' in <code>field4</code>
 +
 
 +
: For details on the <code>merge</code> and <code>match</code> parameters, refer to [[API:EPrints/Search/Field|EPrints::Search::Field]]
 +
 
 +
<pre>  "limit" =&gt; 10</pre>
 +
 
 +
Only return 10 results
  
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<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_list -->
<!-- Pod2Wiki=item_prepare_search -->
+
===list===
====$searchexp = $ds-&gt;prepare_search( %options )====
+
  
Returns a [[API:EPrints/Search|EPrints::Search]] for this dataset with %options.
+
<source lang="perl">$list = $ds->list( $ids )
 +
 
 +
</source>
 +
Returns a [[API:EPrints/List|EPrints::List]] for this dataset for the given $ids list.
  
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<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_search_config -->
<!-- Pod2Wiki=item_search -->
+
===search_config===
====$list = $ds-&gt;search( %options )====
+
  
Short-cut to {{API:PodLink|file=|package_name=|section=prepare_search|text=/prepare_search}}( %options )-&gt;execute.
+
<source lang="perl">$sconf = $dataset->search_config( $searchid )
 +
 
 +
</source>
 +
Retrieve the search configuration $searchid for this dataset. This typically contains a set of fields to search over, order values and rendering parameters.
  
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<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_copyright -->
<!-- Pod2Wiki=item_list -->
+
==COPYRIGHT==
====$list = $ds-&gt;list( $ids )====
+
Copyright 2000-2011 University of Southampton.
  
Returns a [[API:EPrints/List|EPrints::List]] for this dataset for the given $ids list.
+
This file is part of EPrints http://www.eprints.org/.
 +
 
 +
EPrints is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 +
 
 +
EPrints is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
 +
 
 +
You should have received a copy of the GNU Lesser General Public License along with EPrints.  If not, see http://www.gnu.org/licenses/.
  
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<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
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<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=_postamble_ -->
<!-- Pod2Wiki=_postamble_ --><!-- Edit below this comment -->
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<!-- Edit below this comment -->

Latest revision as of 09:56, 22 January 2013

EPrints 3 Reference: Directory Structure - Metadata Fields - Repository Configuration - XML Config Files - XML Export Format - EPrints data structure - Core API - Data Objects


API: Core API

Latest Source Code (3.3, 3.2) | Revision Log | Before editing this page please read Pod2Wiki


NAME

EPrints::DataSet - a set of records with the same metadata scheme


SYNOPSIS

my $dataset = $repository->dataset( "inbox" );
 
print sprintf("There are %d records in the inbox\n",
	$dataset->count);
 
$string = $dataset->base_id; # eprint
$string = $dataset->id; # inbox
 
$dataobj = $dataset->create_dataobj( $data );
$user = $dataset->dataobj( 23 );
 
$search = $dataset->prepare_search( %options );
$list = $dataset->search( %options ); # prepare_search( %options )->execute
$list = $dataset->search; # match ALL
 
$metafield = $dataset->field( $fieldname );
$metafield = $dataset->key_field;
@metafields = $dataset->fields;
 
$dataset->search->map( sub {}, $ctx );
$n = $dataset->search->count; 
$ids = $dataset->search->ids;
$list = $dataset->list( \@ids );


DESCRIPTION

This module describes a dataset.

A repository has several datasets that make up the repository's metadata schema. The list of dataset ids can be obtained from the repository object (see EPrints::Repository).

A normal dataset (eg. "user") has a package associated with it (eg. EPrints::DataObj::User) which must be a subclass of EPrints::DataObj and a number of SQL tables which are prefixed with the dataset name. Most datasets also have a set of associated EPrints::MetaField's which may be optional or required depending on the type eg. books have editors but posters don't but they are both EPrints.

The fields contained in a dataset are defined by the data object and by any additional fields defined in cfg.d. Some datasets don't have any fields.

Some datasets are "virtual" datasets made from others. Examples include "inbox", "archive", "buffer" and "deletion" which are all virtual datasets of of the "eprint" dataset. That is to say "inbox" is a subset of "eprint" and by inference contains EPrints::DataObj::EPrint. You can define your own virtual datasets which opperate on existing datasets.


CREATING CUSTOM DATASETS

New datasets can be defined in a configuration file, e.g.

  $c->{datasets}->{bread} = {
    class => "EPrints::DataObj::Bread",
    sqlname => "bread",
  };

This defines a dataset with the id bread (must be unique). The dataobj package (class) to instantiate objects with is EPrints::DataObj::Bread, which must be a sub-class of EPrints::DataObj. Lastly, the database tables used by the dataset will be called 'bread' or prefixed 'bread_'.

Other optional properties:

  columns - an array ref of field ids to default the user view to
  datestamp - field id to use to sort this dataset
  import - is the dataset importable?
  index - is the dataset text-indexed?
  order - is the dataset orderable?
  virtual - completely virtual dataset (no database tables)

To make one dataset a virtual dataset of another (as 'inbox' is to 'eprint') use the following properties:

  confid - the super-dataset this is a virtual sub-dataset of
  dataset_id_field - the field containing the sub-dataset id
  filters - an array ref of filters to apply when retrieving records

As with system datasets, the EPrints::MetaFields can be defined via EPrints::DataObj/get_system_field_info or via configuration:

  $c->add_dataset_field(
    "bread",
    { name => "breadid", type => "counter", sql_counter => "bread" }
  );
  $c->add_dataset_field(
    "bread",
    { name => "toasted", type => "bool", }
  );
  $c->add_dataset_field(
    "bread",
    { name => "description", type => "text", }
  );

See EPrints::RepositoryConfig/add_dataset_field for details on add_dataset_field.

Creating a fully-operational dataset will require more configuration files. You will probably want at least a workflow, citations for the summary page, search results etc, and permissions and searching settings:

  push @{$c->{user_roles}->{admin}}, qw(
    +bread/create
    +bread/edit
    +bread/view
    +bread/destroy
    +bread/details
  );
  push @{$c->{plugins}->{"Export::SummaryPage"}->{params}->{accept}}, qw(
    dataobj/bread
  );
  $c->{datasets}->{bread}->{search}->{simple} = {
    search_fields => {
      id => "q",
      meta_fields => [qw(
        breadid
        description
      )],
    },
  };


METHODS

Class Methods

Object Methods

$id = $ds->base_id
  $ds = $repo->dataset( "inbox" );
  $id = $ds->base_id; # returns "eprint"

Returns the identifier of the base dataset for this dataset (same as id unless this dataset is virtual).

$metafield = $ds->field( $fieldname )

Returns the EPrints::MetaField from this dataset with the given name, or undef.

$id = $ds->id

Return the id of this dataset.

$n = $ds->count( $session )

Return the number of records in this dataset.

@fields = $ds->fields

Returns a list of the EPrints::MetaFields belonging to this dataset.

$field = $ds->key_field

Return the EPrints::MetaField representing the primary key field.

Always the first field.

$dataobj = $ds->make_dataobj( $epdata )

Return an object of the class associated with this dataset, always a subclass of EPrints::DataObj.

$epdata is a hash of values for fields in this dataset.

Returns $epdata if no class is associated with this dataset.

$obj = $ds->create_dataobj( $data )

Returns a new object in this dataset based on $data or undef on failure.

If $data describes sub-objects then those will also be created.

$dataobj = $ds->dataobj( $id )

Returns the object from this dataset with the given id, or undefined.

$repository = $ds->repository

Returns the EPrints::Repository to which this dataset belongs.

$searchexp = $ds->prepare_search( %options )

Returns a EPrints::Search for this dataset with %options.

$list = $ds->search( %options )

Short-cut to prepare_search( %options )->execute.

  • satisfy_all
   satisfy_all"=>1
Satify all conditions specified. 0 means satisfy any of the conditions specified. Default is 1
  • staff
  "staff"=>1
Do search as an adminstrator means you get everything back
  • custom_order
  "custom_order" => "field1/-field2/field3"
Order the search results by field order. prefixing the field name with a "-" results in reverse ordering
  • filters
  "filters" => \@(
                         { meta_fields=>[ "field1", "field2" "document.field3" ],
                           merge=>"ANY", match=>"EX",
                           value=>"bees"
                         },
                         { meta_fields=>[ "field4" ],
                           value=> qw( honey ),
                           match=>"IN"
                         }
                       );
This searchs for 'bees' in field1 or field2 or document.field3, and 'honey' in field4
For details on the merge and match parameters, refer to EPrints::Search::Field
  "limit" => 10

Only return 10 results


list

$list = $ds->list( $ids )

Returns a EPrints::List for this dataset for the given $ids list.


search_config

$sconf = $dataset->search_config( $searchid )

Retrieve the search configuration $searchid for this dataset. This typically contains a set of fields to search over, order values and rendering parameters.


COPYRIGHT

Copyright 2000-2011 University of Southampton.

This file is part of EPrints http://www.eprints.org/.

EPrints is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

EPrints is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with EPrints. If not, see http://www.gnu.org/licenses/.