public function setNullablePositionColumn(SchemaSetupInterface $setup)
    {
        $setup->getConnection()->modifyColumn(
            $setup->getTable('smile_virtualcategory_catalog_category_product_position'),
            'position',
            [
                'type'     => \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
                'nullable' => true,
                'comment'  => 'Position',
            ]
        );
    }
public function setNullablePositionColumn(SchemaSetupInterface $setup)
    {
        $setup->getConnection()->modifyColumn(
            $setup->getTable('smile_virtualcategory_catalog_category_product_position'),
            'position',
            [
                'type'     => \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
                'nullable' => true,
                'comment'  => 'Position',
            ]
        );
    }
public function setNullablePositionColumn ( SchemaSetupInterface $ setup ) { $ setup -> getConnection ( ) -> modifyColumn ( $ setup -> getTable ( 'smile_virtualcategory_catalog_category_product_position' ) , 'position' , [ 'type' => \ Magento \ Framework \ DB \ Ddl \ Table :: TYPE_INTEGER , 'nullable' => true , 'comment' => 'Position' , ] ) ; }
Set the 'position' column of 'smile_virtualcategory_catalog_category_product_position' to nullable=true.

@param \Magento\Framework\Setup\SchemaSetupInterface $setup Setup interface
Set the position column of smile_virtualcategory_catalog_category_product_position to nullable = true .