magento2 数据库查询

调试数据集 Select

$collection = $this->_objectManager->get( 'Magento\Catalog\Model\ProductFactory' )->create()->getCollection();
echo $collection->load()->getSelectSql( true );

通过 Select 获取数据

$conn = $this->_objectManager->get( 'Magento\Framework\App\ResourceConnection' )->getConnection();
$tblMain = $conn->getTableName( 'cms_page' );
$tblStore = $conn->getTableName( 'cms_page_store' );

$select = $conn->select()
        ->distinct()
        ->from( [ 'page' => $tblMain ], [ 'page_id', 't' => 'title' ] )
        ->join( [ 'store' => $tblStore ], 'store.page_id = page.page_id', [ 'sid' => 'store_id' ] )
        ->where( 'is_active = ?', '1' )
        ->order( 'title ASC' )
        ->limit( 5, 1 );

$data = $conn->fetchAll( $select );

聚合查询（SUM）

$conn = $this->_objectManager->get( 'Magento\Framework\App\ResourceConnection' )->getConnection();
$tbl = $conn->getTableName( 'sales_order_item' );

// 所有记录总计
$select = $conn->select()
        ->from( $tbl, [ 'total' => new \Zend_Db_Expr( 'SUM( qty_ordered )' ) ] )
        ->where( 'order_id = ?', '1' );
$result = $conn->fetchOne( $select );

// 各局部统计
$select = $conn->select()
        ->from( $tbl, [ 'order_id', 'total' => new \Zend_Db_Expr( 'SUM( qty_ordered )' ) ] )
        ->group( 'order_id' )
        ->having( 'order_id != ?', '1' );
$result = $conn->fetchAll( $select );

更新数据

/** @var $conn \Magento\Framework\App\ResourceConnection */
/** @var $storeId int */
/** @var $ids array */

$tbl = $conn->getTableName( 'sales_order_item' );

// 插入数据
$conn->insert( $tbl, [ 'field_one' => $fieldOne, 'field_two' => $fieldTwo, 'field_three' => $fieldThree ] );

// 插入数据，碰到已存在的记录（primary / unique）则只更新指定的字段
$conn->insertOnDuplicate( $tbl, [ 'field_one' => $fieldOne, 'field_two' => $fieldTwo, 'field_three' => $fieldThree ], [ 'field_three' ] );

// 更新数据
$conn->update( $tbl, [ 'field_one' => $fieldOne, 'field_two' => $fieldTwo ], $conn->quoteInto( 'store_id IN (?)', $storeId ) );

// 删除数据
$conn->delete( $tbl, [ 'id IN (?)' => $ids ] );

Model

/* @var \Magento\Directory\Model\ResourceModel\Region\Collection $collection */
$collection = $objectManager->get('Magento\Directory\Model\ResourceModel\Region\Collection');
$collection->getSelect()
    ->where('main_table.region_id = ?', 1)
    ->where('main_table.country_id=?', 'US');
foreach($collection as $row) {
    echo $row->getData('default_name');
}