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Wez Furlong
d4a158260b
by name, even when multiple columns have the same name:
$sql = "SELECT 1 a, 2 a, 3 b, 4 c, 5 d, 6 c, 7 a";
echo "$sql\n";
print_r($db->query($sql)->fetchAll(PDO_FETCH_NAMED));
Array
(
[0] => Array
(
[a] => Array
(
[0] => 1
[1] => 2
[2] => 7
)
[b] => 3
[c] => Array
(
[0] => 4
[1] => 6
)
[d] => 5
)
)
Also added two new attributes for use at prepare time;
PDO_ATTR_FETCH_TABLE_NAMES and PDO_ATTR_FETCH_CATALOG_NAMES instruct the driver
that the names of the columns that they return to PDO should include the table
and catalog names respectively. Both attributes may be used together or
independently. The catalog, table and column name components should be
separated by a . character.
$Id$
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