Using Database Service¶

Instantiation¶

The database service was designed to be of type singleton. Therefore it's highly recommended to instantiate this Service using the makeInstance method of GeneralUtility instead of using the "new" keyword (whereby classes should never been instantiated via "new", please make us of makeInstance or the ObjectManager instead). This will ensure the Database Service will exist only once, what may increase processing speed significantly:

$DatabaseService = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(
    \DanielHaring\Crystalis\Service\DatabaseService::class);

Accessing database¶

You may come to that point where you want to have database access before the TYPO3_DB class was initiated. For this purpose the Database Service is able to establish it's own database connection, which is done automatically if a query was sent and the TYPO3_DB class is not present. You can get this connection by simply calling the following:

\DanielHaring\Crystalis\Service\DatabaseService::getDatabaseConnection();

The returning object behaves exactly the same as TYPO3_DB does, thus allowing you to make familiar queries:

$result = \DanielHaring\Crystalis\Service\DatabaseService::getDatabaseConnection()
    ->exec_SELECTquery('foo,bar,baz', 'tx_foobar_baz', 'foo=\'bar\'');

A new database connection will be established using the Crystalis General Utility class. If you do not need all the specific functions provided by the Database Service, you can obtain a database connection by directly calling the respective method:

$DB = \DanielHaring\Crystalis\Utility\GeneralUtility::obtainDatabaseConnection();
$DB->exec_SELECTquery('foo,bar,bat', 'tx_foobar_baz', 'foo=\'bar\'');

No matter which way you choose when accessing the database, a new connection only will be established if it is really necessary. Meaning if TYPO3_DB already was initiated or a new connection was established previously, the existing one will be used instead of creating a new one.

Public member functions¶