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df79b9b27a
* get_class_name is now only used for displaying the class name in debugging functions like var_dump, print_r, etc. It is no longer used in get_class() etc. * As it is no longer used in get_parent_class() the parent argument is now gone. This also fixes incorrect parent classes being reported in COM. * get_class_name is now always required (previously some places made it optional and some required it) and is also required to return a non-NULL value. * Remove zend_get_object_classname. This also fixes a number of potential leaks due to incorrect usage of this function.
$Id$
PHP Data Objects
================
Concept: Data Access Abstraction
Goals:
1/ Be light-weight
2/ Provide common API for common database operations
3/ Be performant
4/ Keep majority of PHP specific stuff in the PDO core (such as persistent
resource management); drivers should only have to worry about getting the
data and not about PHP internals.
Transactions and autocommit
===========================
When you create a database handle, you *should* specify the autocommit
behaviour that you require. PDO will default to autocommit on.
$dbh = new PDO("...", $user, $pass, array(PDO_ATTR_AUTOCOMMIT => true));
When auto-commit is on, the driver will implicitly commit each query as it is
executed. This works fine for most simple tasks but can be significantly
slower when you are making a large number of udpates.
$dbh = new PDO("...", $user, $pass, array(PDO_ATTR_AUTOCOMMIT => false));
When auto-commit is off, you must then use $dbh->beginTransaction() to
initiate a transaction. When your work is done, you then call $dbh->commit()
or $dbh->rollBack() to persist or abort your changes respectively. Not all
databases support transactions.
You can change the auto-commit mode at run-time:
$dbh->setAttribute(PDO_ATTR_AUTOCOMMIT, false);
Regardless of the error handling mode set on the database handle, if the
autocommit mode cannot be changed, an exception will be thrown.
Some drivers will allow you to temporarily disable autocommit if you call
$dbh->beginTransaction(). When you commit() or rollBack() such a transaction,
the handle will switch back to autocommit mode again. If the mode could not
be changed, an exception will be raised, as noted above.
When the database handle is closed or destroyed (or at request end for
persistent handles), the driver will implicitly rollBack(). It is your
responsibility to call commit() when you are done making changes and
autocommit is turned off.
vim:tw=78:et