Configuration ============= The first thing you need to know about Idiorm is that *you don’t need to define any model classes to use it*. With almost every other ORM, the first thing to do is set up your models and map them to database tables (through configuration variables, XML files or similar). With Idiorm, you can start using the ORM straight away. Setup ~~~~~ First, ``require`` the Idiorm source file: :: require_once 'idiorm.php'; Then, pass a *Data Source Name* connection string to the ``configure`` method of the ORM class. This is used by PDO to connect to your database. For more information, see the `PDO documentation`_. :: ORM::configure('sqlite:./example.db'); You may also need to pass a username and password to your database driver, using the ``username`` and ``password`` configuration options. For example, if you are using MySQL: :: ORM::configure('mysql:host=localhost;dbname=my_database'); ORM::configure('username', 'database_user'); ORM::configure('password', 'top_secret'); Also see “Configuration” section below. Configuration ~~~~~~~~~~~~~ Other than setting the DSN string for the database connection (see above), the ``configure`` method can be used to set some other simple options on the ORM class. Modifying settings involves passing a key/value pair to the ``configure`` method, representing the setting you wish to modify and the value you wish to set it to. :: ORM::configure('setting_name', 'value_for_setting'); A shortcut is provided to allow passing multiple key/value pairs at once. :: ORM::configure(array( 'setting_name_1' => 'value_for_setting_1', 'setting_name_2' => 'value_for_setting_2', 'etc' => 'etc' )); Database authentication details ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Settings: ``username`` and ``password`` Some database adapters (such as MySQL) require a username and password to be supplied separately to the DSN string. These settings allow you to provide these values. A typical MySQL connection setup might look like this: :: ORM::configure('mysql:host=localhost;dbname=my_database'); ORM::configure('username', 'database_user'); ORM::configure('password', 'top_secret'); Or you can combine the connection setup into a single line using the configuration array shortcut: :: ORM::configure(array( 'mysql:host=localhost;dbname=my_database', 'username' => 'database_user', 'password' => 'top_secret' )); Result sets ^^^^^^^^^^^ Setting: ``return_result_sets`` Collections of results can be returned as an array (default) or as a result set. See the `find_result_set()` documentation for more information. :: ORM::configure('return_result_sets', true); // returns result sets .. note:: It is recommended that you setup your projects to use result sets as they are more flexible. PDO Driver Options ^^^^^^^^^^^^^^^^^^ Setting: ``driver_options`` Some database adapters require (or allow) an array of driver-specific configuration options. This setting allows you to pass these options through to the PDO constructor. For more information, see `the PDO documentation`_. For example, to force the MySQL driver to use UTF-8 for the connection: :: ORM::configure('driver_options', array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8')); PDO Error Mode ^^^^^^^^^^^^^^ Setting: ``error_mode`` This can be used to set the ``PDO::ATTR_ERRMODE`` setting on the database connection class used by Idiorm. It should be passed one of the class constants defined by PDO. For example: :: ORM::configure('error_mode', PDO::ERRMODE_WARNING); The default setting is ``PDO::ERRMODE_EXCEPTION``. For full details of the error modes available, see `the PDO set attribute documentation`_. PDO object access ^^^^^^^^^^^^^^^^^ Should it ever be necessary, the PDO object used by Idiorm may be accessed directly through ``ORM::get_db()``, or set directly via ``ORM::set_db()``. This should be an unusual occurance. After a statement has been executed by any means, such as ``::save()`` or ``::raw_execute()``, the ``PDOStatement`` instance used may be accessed via ``ORM::get_last_statement()``. This may be useful in order to access ``PDOStatement::errorCode()``, if PDO exceptions are turned off, or to access the ``PDOStatement::rowCount()`` method, which returns differing results based on the underlying database. For more information, see the `PDOStatement documentation`_. Identifier quote character ^^^^^^^^^^^^^^^^^^^^^^^^^^ Setting: ``identifier_quote_character`` Set the character used to quote identifiers (eg table name, column name). If this is not set, it will be autodetected based on the database driver being used by PDO. ID Column ^^^^^^^^^ By default, the ORM assumes that all your tables have a primary key column called ``id``. There are two ways to override this: for all tables in the database, or on a per-table basis. Setting: ``id_column`` This setting is used to configure the name of the primary key column for all tables. If your ID column is called ``primary_key``, use: :: ORM::configure('id_column', 'primary_key'); Setting: ``id_column_overrides`` This setting is used to specify the primary key column name for each table separately. It takes an associative array mapping table names to column names. If, for example, your ID column names include the name of the table, you can use the following configuration: :: ORM::configure('id_column_overrides', array( 'person' => 'person_id', 'role' => 'role_id', )); Query logging ^^^^^^^^^^^^^ Setting: ``logging`` Idiorm can log all queries it executes. To enable query logging, set the ``logging`` option to ``true`` (it is ``false`` by default). When query logging is enabled, you can use two static methods to access the log. ``ORM::get_last_query()`` returns the most recent query executed. ``ORM::get_query_log()`` returns an array of all queries executed. Query caching ^^^^^^^^^^^^^ Setting: ``caching`` Idiorm can cache the queries it executes during a request. To enable query caching, set the ``caching`` option to ``true`` (it is ``false`` by default). When query caching is enabled, Idiorm will cache the results of every ``SELECT`` query it executes. If Idiorm encounters a query that has already been run, it will fetch the results directly from its cache and not perform a database query. Warnings and gotchas '''''''''''''''''''' - Note that this is an in-memory cache that only persists data for the duration of a single request. This is *not* a replacement for a persistent cache such as `Memcached`_. - Idiorm’s cache is very simple, and does not attempt to invalidate itself when data changes. This means that if you run a query to retrieve some data, modify and save it, and then run the same query again, the results will be stale (ie, they will not reflect your modifications). This could potentially cause subtle bugs in your application. If you have caching enabled and you are experiencing odd behaviour, disable it and try again. If you do need to perform such operations but still wish to use the cache, you can call the ``ORM::clear_cache()`` to clear all existing cached queries. - Enabling the cache will increase the memory usage of your application, as all database rows that are fetched during each request are held in memory. If you are working with large quantities of data, you may wish to disable the cache. .. _PDO documentation: http://php.net/manual/en/pdo.construct.php .. _the PDO documentation: http://www.php.net/manual/en/pdo.construct.php .. _the PDO set attribute documentation: http://uk2.php.net/manual/en/pdo.setattribute.php .. _PDOStatement documentation: http://www.php.net/manual/en/class.pdostatement.php .. _Memcached: http://www.memcached.org/