Checking for duplicate keys in Doctrine

30 Jan 2013

Doctrine doesn’t seem to have an inbuilt mechanism for checking for duplicate entries; one solution thrown around the web is to simply try catch the PDOException code 23000.

Here is a solution I use, which makes use of the MetadataFactory to retrieve the unique constraints. It then simply tries to find an existing entity based on the same values:

public function isDuplicateEntity(Model $model) 
{   
    $em = $this->getEntityManager;
    $cmf = $em->getMetadataFactory();
    $class = $cmf->getMetadataFor(get_class($model));
  
    if(isset($class->table['uniqueConstraints'])) {
        $uniqueColumns = array();
        $uniqueConstraints = $class->table['uniqueConstraints'];    
        
        foreach($uniqueConstraints as $constraintName => $constraintSection) {
                foreach($constraintSection['columns'] as $column) {
                $value = $model->{$column};
                    $uniqueColumns[$column] = $value;
                }
        }
        $className = get_class($model);
        $unique = $em->getRepository($className)->findOneBy($uniqueColumns);
        
        if($unique instanceof $className) {
            $model->id = $unique->id;
            return true;
        }
    }
    return false;
}