Doctrine: ON DUPLICATE KEY UPDATE

问题:

How can I write an INSERT doctrine query with option ON DUPLICATE KEY UPDATE?

回答1:

The problem is that this is a MySQL specific problem so it will not be directly covered by Doctrine.

As a comment mentioned, you would need to write a RawSQL Query for this. This would be the easiest way.

If you want it more sophisticated and truely DB independent, look into Events and it's possibilities. Before the actual query is executed, you can check for an existence and if it exists, act accordingly.

An ORM/PHP independent way is to write a stored procedure/trigger that handles this problem database side.

回答2:

for Symfony 2 use raw sql:

$em->getConnection()->prepare("INSERT INTO table SET 
    some_fields = "some data", created_at = NOW() 
    ON DUPLICATE KEY UPDATE
    some_fields = "some data", updated_at = NOW()
")->execute();

回答3:

I had the same problem and after investigating a bit it looks like Doctrine doesn't do it. My solution was to do a findBy before my insert to see if any records exist with the unique fields. If this returns an entity then I update that entity and persist it instead of creating a new entity to persist.

If you are concerned about performance then this is not ideal as we are doing a select before every insert. However since Doctrine is database agnostic it is the only alternative to locking yourself to MySQL. It's one of those tradeoffs: do you want performance or portability.

回答4:

You can use function like this to build and execute raw sql:

 /**
 * 
 * insertWithDuplicate('table_name', array('unique_field_name' => 'field_value', 'field_name' => 'field_value'), array('field_name' => 'field_value'))
 * 
 * @param string $tableName
 * @param array $insertData 
 * @param array $updateData
 * 
 * @return bolean
 */
public function insertWithDuplicate($tableName, $insertData, $updateData) {
    $columnPart = '';
    $valuePart = '';
    $columnAndValue = '';
    foreach ($insertData as $key => $value) {
        $value = str_replace(array('"', "'"), array('\"', "\'"), $value);
        $columnPart .= "`" . $key . "`" . ',';
        is_numeric($value) ? $valuePart .= $value . ',' : $valuePart .= "'" . $value . "'" . ',';
    }
    foreach ($updateData as $key => $value) {
        $value = str_replace(array('"', "'"), array('\"', "\'"), $value);
        is_numeric($value) ? $columnAndValue .= $key . ' = ' . $value . ',' : $columnAndValue .= "`" . $key . "`" . ' = ' . "'" . $value . "'" . ',';
    }
    $_columnPart = substr($columnPart, 0, strlen($columnPart) - 1);
    $_valuePart = substr($valuePart, 0, strlen($valuePart) - 1);
    $_columnAndValue = substr($columnAndValue, 0, strlen($columnAndValue) - 1);
    $query = "INSERT INTO " . $tableName .
            " (" . $_columnPart . ") "
            . "VALUES" .
            " (" . $_valuePart . ") "
            . "ON DUPLICATE KEY UPDATE " .
            $_columnAndValue;
    return $this->entityManager->getConnection()
                    ->prepare($query)->execute();
}

回答5:

I created a doctrine dbal wrapper to do that. It can be used with DoctrineBundle with the dbal wrapper_class option.

https://github.com/iJanki/doctrine-mysql-dbal-extensions

回答6:

You can't. It's not supported by Doctrine right now.

What you could do is to imitate what MySQL does by checking if the entity exists and update/create it accordingly:

$em = $this->getEntityManager();

// Prevent race conditions by putting this into a transaction.
$em->transactional(function($em) use ($content, $type) {
  // Use pessimistic write lock when selecting.
  $counter = $em->createQueryBuilder()
    ->select('MyBundle:MyCounter', 'c')
    ->where('c.content = :content', 'c.type = :type')
    ->setParameters(['content' => $content, 'type' => $type])
    ->setLockMode(\Doctrine\DBAL\LockMode::PESSIMISTIC_WRITE);
    ->getQuery()
    ->getResult()
  ;

  // Update if existing.
  if ($counter) {
    $counter->increase();
  } else {
    // Create otherwise.
    $newCounter = new Counter($content, $type, 1);
    $em->persist($newCounter);
  }
});

If the record exists PESSIMISTIC_WRITE makes sure that it's not updated by anyone (e.g., other threads) while we're updating it.

Although you need to check for the entity's existence on every update, it's a simple reproduction of "update if existing and create if not".

As pointed out in the comments this does not prevent a race condition if the record doesn't exist: If a row with the same key(s) gets inserted between the select and the insert you're running into a duplicate key exception.

But given the constraints that this needs to be DB independent and thus written using Doctrine and not using native SQL it may help in some cases.

References:

• Database Administrators: Putting a Select statement in a transaction
• MySQL Reference Manual: Locking Reads (SELECT ... FOR UPDATE)
• Doctrine 2 ORM documentation: Transactions and Concurrency
• Stackoverflow: Doctrine2 ORM select for update

回答7:

I wrote simple solution for me. Just created AbstractRepository class which is parent class of all Repositories(for example UserRepository) and created next method:

 public function onDuplicateUpdate($insertFields, $updateFields)
    {
        $table = $this->getEntityManager()->getClassMetadata($this->getEntityName())->getTableName();
        $sql = 'INSERT INTO '.$table;
        $sql .= '(`'.implode('`,`', array_flip($insertFields)).'`) ';
        $sql .= 'VALUES("'.implode('","', $insertFields).'") ';
        $sql .= 'ON DUPLICATE KEY UPDATE ';
        foreach($updateFields as $column => $value) {
            $sql .= '`'.$column . '` = "'. $value.'"';
        }
        $stmt = $this->getEntityManager()->getConnection()->prepare($sql);
        $stmt->execute();
    }

You can use this code like this:

$this->getEntityManager()
           ->getRepository('User')
           ->onDuplicateUpdate(['column1' => 'user_reminder_1', 'column2' => 235], ['column2' => 255]);

回答8:

In case this helps, you can extend the query builder to append arbitrary SQL (obviously, this may not work across PDO engines):

class MyQB extends QueryBuilder {

    private $append = '';

    /**
     * {@inheritdoc}
     */
    public function getSQL() {
        return parent::getSQL() . $this->append;
    }

    /**
     * Append raw SQL to the output query
     *
     * @param string $sql SQL to append. E.g. "ON DUPLICATE ..."
     *
     * @return self
     */
    public function appendSql($sql) {
        $this->append = $sql;
        return $this;
    }
}

回答9:

You have three options.

The first option is to drop down to SQL. Then you can use all the features your RDBMS of choice provides. But many programmers don't want to drop down to SQL unless absolutely necessary.

The second option is to lock on a related row in another table. For instance, if the entity you're inserting has a unique key per user, you could do a lock on the user you're inserting/updating the entity for. The problem with this solution is that it doesn't work for root entities like User itself because you can't lock a row that doesn't exist yet.

The third option is to just catch the duplicate key error/exception. That is, you don't check if a row with a particular key already exists; instead, you just attempt to insert it. If it succeeds, all is good. If it fails with the duplicate key error/exception, you catch it and update the existing row. This solution is the best because it avoids an extra SELECT query before each insertion that's a constant overhead for the low probability of hitting a race condition. And it's the best because it works for both root and non-root entities.