lib/components/dataInterface/connectors/db/DataSource.php
protected function loadForeignDataItems()
    {
        $this->_foreignDataItems = [];
        if ($this->lazyForeign) {
            $primaryKeys = $this->foreignModel->findPrimaryKeys($this->settings['foreignPullParams']);
            foreach ($primaryKeys as $primaryKey) {
                $this->createForeignDataItem(null, ['foreignPrimaryKey' => $primaryKey]);
            }
        } else {
            $foreignModels = $this->foreignModel->findAll($this->settings['foreignPullParams']);
            foreach ($foreignModels as $key => $model) {
                $this->createForeignDataItem($model, []);
            }
        }
    }
protected function loadForeignDataItems()
    {
        $this->_foreignDataItems = [];
        if ($this->lazyForeign) {
            $primaryKeys = $this->foreignModel->findPrimaryKeys($this->settings['foreignPullParams']);
            foreach ($primaryKeys as $primaryKey) {
                $this->createForeignDataItem(null, ['foreignPrimaryKey' => $primaryKey]);
            }
        } else {
            $foreignModels = $this->foreignModel->findAll($this->settings['foreignPullParams']);
            foreach ($foreignModels as $key => $model) {
                $this->createForeignDataItem($model, []);
            }
        }
    }
Load the foreign data items, either lazily or not.