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Data Cube

The result of a Query is the apex CubeCell that aggregates all the data in the result.

Class Diagram​

Data cube result class diagram Data cube result class diagram

Definition​

A CubeCell contains coordinates of dimension and a collection of measures.

Coordinates are a collection of dimensions, each of which is a property of the summary entity. The coordinates instance also contains the dice predicate, which is the filter expression applied to the query.

Measures are the properties that represent the aggregated values, such as count, price.

Example: A CubeCell may contain coordinates with dimensions like:

  • time.year = 2023
  • country = DE
  • category = electronics

In such a CubeCell, the measures might contain values of:

  • count = 20
  • price = 1000.00

It means that in the year 2023, there were 20 orders from Germany in the electronics category, with a total price of 1000.00.

Example Query​

use Doctrine\Common\Collections\Criteria;
use Rekalogika\Analytics\Contracts\SummaryManager;

/** @var SummaryManager $summaryManager */

$apexCube = $summaryManager
    ->createQuery()
    ->from(OrderSummary::class) // the summary entity class name
    ->withDimensions('country', 'category') // dimensions
    ->dice(Criteria::expr()->gte('time.year', 2023)) // filter expression
    ->getResult();

The getResult() method above returns the apex CubeCell that aggregates all data in the year 2023 and beyond. Then, you can drill down or slice the cube to get more specific CubeCell objects that involve the country and category dimensions.

Because the query above only specifies the country and category dimensions, you may only drill down or slice by those dimensions. If you try to drill down or slice by a dimension that is not included in the query, it will throw an exception.

drillDown() method​

The drillDown() method allows you to drill down into a specific dimension. It adds a new dimension to the coordinates and returns all the possible CubeCell, each with a unique value for the specified dimension.

use Rekalogika\Analytics\Contracts\Result\CubeCell;

/** @var CubeCell $year2025 */

$year2025Count = $year2025->getMeasures()->get('count')->getValue(); // e.g. 20
$year2025InCountries = $year2025->drillDown('customerCountry');

$totalCount = 0;

foreach ($year2025InCountries as $year2025InACountry) {
    $totalCount += $year2025InACountry->getMeasures()->get('count')->getValue();
}

assert($totalCount === $year2025Count);

In the above example, if the $year2025Cube contains the number 20 as the count value, the $year2025InCountries might contain several CubeCell objects, each having a different country, such as DE, US, and FR, with their count values adding to exactly 20.

drillDown() drillDown()

tip

The drillDown() method can also accept an array of dimension names to drill down multiple dimensions at once. You will get a cartesian product of all the possible combinations of the specified dimensions.

rollUp() method​

The rollUp() method is the reverse of drillDown(). It allows you to roll up the data cube to a higher level of aggregation. It returns the CubeCell that represents the rolled-up data. rollUp() basically removes the specified dimension from the coordinates and aggregates the measures accordingly.

use Rekalogika\Analytics\Contracts\Result\CubeCell;

/** @var CubeCell $year2025InGermany */

$germany = $year2025InGermany->rollUp('time.year');

rollUp() rollUp()

tip

The rollUp() method can also accept an array of dimension names to roll up multiple dimensions at once.

slice() method​

The slice() method allows you to slice the data cube by a specific dimension and member. It adds a new dimension to the coordinates and returns the corresponding CubeCell.

use Rekalogika\Analytics\Contracts\Result\CubeCell;

/** @var CubeCell $year2025 */
/** @var Country $france */

$year2025InFrance = $year2025->slice('country', $france);

slice() slice()

find() method​

find() is similar to slice(), but it matches the value using a "fuzzy", non-exact comparison.

use Rekalogika\Analytics\Contracts\Result\CubeCell;

/** @var CubeCell $year2025 */

$year2025InFrance = $year2025->find('country', 'fr');

In the above example, if the entity Country has its __toString() method defined to return the country code, find() will try to match the value 'fr' to that.

find() also accepts a callable as the second argument. The callable should take a single argument and return a boolean value indicating whether the value matches the criteria.

pivot() method​

The pivot() method allows you to change the order of dimensions in the coordinates. It takes one or more dimension names as arguments and rearranges the dimensions in the specified order.

pivot() pivot()

dice() method​

The dice() method is meant to allow you to remove or update the dice predicate. However, it is not implemented yet.