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This document contains information for an outdated version (2.4) and may not be maintained any more.

If some of your projects still use this version, consider upgrading as soon as possible.

DataObjectSet

Introduction

This class represents a set of DataObjects, such as the results of a query. It is the base for all datamodel-related querying. It implements the Iterator interface introduced in PHP5.

Relations (has_many/many_many) are described in ComponentSet, a subclass of DataObjectSet.

Usage

Getting the size

$mySet->Count();

Getting an single element

$myFirstDataObject = $mySet->First();
$myLastDataObject = $mySet->Last();

Getting multiple elements

$mySpecialDataObjects = $mySet->find('Status', 'special');
$startingFromTen = $mySet->getOffset(10);
$tenToTwenty = $mySet->getRange(10, 10);

Getting one property

$myIDArray = $mySet->column('ID');

Grouping

You can group a set by a specific column. Consider using SQLQuery with a GROUP BY statement for enhanced performance.

$groupedSet = $mySet->groupBy('Lastname');

Sorting

Sort a set by a specific column.

$mySet->sort('Lastname'); //ascending
$mySet->sort('Lastname', 'DESC'); //descending

This works on the object itself, so do NOT do something like this:

$sortedSet = $mySet->sort('Lastname'); //ascending

Merge with other DataObjectSets

$myFirstSet->merge($mySecondSet);
// $myFirstSet now contains all combined values

Mapping for Dropdowns

When using DropdownField and its numerous subclasses to select a value from a set, you can easily map the records to a compatible array:

$map = $mySet->toDropDownMap('ID', 'Title');
$dropdownField = new DropdownField('myField', 'my label', $map);

Converting to array

$myArray = $mySet->toArray();

Checking for existence

It is good practice to check for empty sets before doing any iteration.

$mySet = DataObject::get('Players');
if($mySet->exists()) foreach($mySet as $player)

Paging

DataObjects have native support for dealing with pagination. See setPageLimits, setPageLength, etc.

FIXME Complete pagination documentation

API Documentation

DataObjectSet

Comments

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