Closed
Description
Feature Request
| Q | A |
|---|---|
| New Feature | yes |
| RFC | no |
| BC Break | no |
Summary
PHP 7.2 added support for specifying different bind types for unicode and non-unicode string data: https://wiki.php.net/rfc/extended-string-types-for-pdo
This is a major improvement over the default (PDO::PARAM_STR) which binds strings as unicode data. In the past, the inability for PHP to handle this has led to performance problems in certain cases. For example if we have something like:
$statement = $connection->prepare(
'SELECT * FROM ... WHERE myVarcharColumn = :value' -- will bind as N'...'
);
$statement->bindValue(':value', $myVarcharValue);
$statement->execute();If there's an index on myVarcharColumn SQL won't be able to use the index effectively since the binding will be an NVARCHAR string and force an implicit conversation.
Does the team have a plan to support this binding in the future? We actually implemented this internally in a wrapper we have DBAL. I'm happy to open a PR if the team supports this feature:
use Doctrine\DBAL\Platforms\AbstractPlatform;
use Doctrine\DBAL\Types\StringType;
use PDO;
class VarcharType extends StringType
{
public const NAME = 'varchar';
public function getSQLDeclaration(array $field, AbstractPlatform $platform)
{
$length = $field['length'] ?? $platform->getVarcharDefaultLength();
return 'VARCHAR(' . $length . ')';
}
public function getBindingType()
{
return PDO::PARAM_STR | PDO::PARAM_STR_CHAR;
}
public function getName()
{
return static::NAME;
}
}