Principles

Functions availables

• Natives functions
• User functions

Functions on Select Statement

$df->select('colA')->whereColumn('colB', 'foo')->sum();

Aggregation with a Group by

$df->groupBy('city', Sum::col('population', as: 'totalPopulation'));
$df->selectAll()->whereColumn('city', equal: 'Paris')->groupBy('district', Sum::col('population', as: 'totalPopulation'));