Update EAV attribute value in custom admin module

Question

I have a form container with save button . This is the method that the save button call.

public function saveAction(){
    $userId = Mage::getSingleton('admin/session')->getUser()->getId();
    $user = Mage::getModel('admin/user')->load($userId);
    $idSetting=$user->getShopsetting_entity_id();
    $setting=Mage::getSingleton('Name_Module/shopSetting')->load($idSetting);

    $setting->setData($this->getRequest()->getParam('shopSetting'));
    $setting->save();

    return $this->_redirect('*/*/index');
}

This method create another element in shopSetting_entity, but I want the attributes value is modified.

I also try using

$setting->setAttributeName($shopSetting['attribute_name']);
$setting->save();

But in this case Magento add a row in shopSetting_entity_int with same entity_type_id,attribute_id,store_id,entity_id and does not modify the old one.

(int is the type of attribute_name)

I also try with

$setting->setAttributeName($shopSetting['attribute_name']);
$setting->getResource()->saveAttribute($setting,'attribute_name');

But the result is always the same.

In particular case of the method saveAttribute of Mage_Eav_Model_Entity_Abstract I note that this method distinguishes between the update and insertion, this is the code:

....
 $select = $adapter->select()
                ->from($table, 'value_id')
                ->where($where);
            $origValueId = $adapter->fetchOne($select);

            if ($origValueId === false && ($newValue !== null)) {
                $this->_insertAttribute($object, $attribute, $newValue);
            } elseif ($origValueId !== false && ($newValue !== null)) {
                $this->_updateAttribute($object, $attribute, $origValueId, $newValue);
            } elseif ($origValueId !== false && ($newValue === null)) {
                $adapter->delete($table, $where);
            }
            $this->_processAttributeValues();
            $adapter->commit();
...

but _insertAttribute and _updateAttribute call the same method _saveAttribute

    protected function _insertAttribute($object, $attribute, $value)
{
    return $this->_saveAttribute($object, $attribute, $value);
}

....

    protected function _updateAttribute($object, $attribute, $valueId, $value)
{
    return $this->_saveAttribute($object, $attribute, $value);
}

maybe there's a bug

Answer 1

If you call setData() with an array, the complete data gets replaced, this includes the ID.

So, if the result of $this->getRequest()->getParam('shopSetting') does not contain the ID, a new entity is created.

You probably are looking for addData() which sets only the attributes that exist in the passed array and leaves the rest as it is.

Answer 2

I have detected the same problem on one of my custom EAV entity types.

When Magento updates EAV values, it uses an INSERT INTO with ON DUPLICATE KEY UPDATE to update the data in the eav tables.

An example query to update a value looks like this:

INSERT INTO `download_entity_varchar` 
(`entity_type_id`,`entity_id`,`attribute_id`,`value`)
VALUES (9, 6, 446, 'this is a value')
ON DUPLICATE KEY UPDATE `value` = VALUES(`value`)

The MySQL documenation says:

If you specify ON DUPLICATE KEY UPDATE, and a row is inserted that would cause a duplicate value in a UNIQUE index or PRIMARY KEY, MySQL performs an UPDATE of the old row.

Comparing my custom table indizes to the indizes of catalog_product_entity_varchar I realized that there is one index missing on my table: the unique index over the columns entity_id, attribute_id and store_id.

So I added an unique index to my table after removing all duplicate entries, with this:

ALTER TABLE `download_entity_varchar`
ADD UNIQUE KEY `UNQ_DOWNLOAD_ENTITY_VARCHAR_ENTITY_ID_ATTRIBUTE_ID_STORE_ID` 
(`entity_id`,`attribute_id`,`store_id`)

If you want to do it programmatically with an upgrade script (usually the smarter way), you just have to add the following lines and adjust the table name:

$table = 'download_entity_varchar';
$fields = ['entity_id', 'attribute_id', 'store_id'];
$indexType = Varien_Db_Adapter_Interface::INDEX_TYPE_UNIQUE;

$indexName = $installer->getIdxName($table, $fields, $indexType);
$installer->getConnection()->addIndex($table, $indexName, $fields, $indexType);

This has to be done for each value type table, which are

• _entity_char
• _entity_datetime
• _entity_decimal
• _entity_int
• _entity_text
• _entity_varchar

After doing that, the values get updated correctly.

For me it seems to be a bug in Magento, that the unique index is not created in Mage_Eav_Model_Entity_Setup::createEntityTables.