Transaction

API reference › yii › db › Transaction

class	`yii\db\Transaction`
Extends	`yii\base\BaseObject`
Implements	`yii\base\Configurable`
Since	2.0
Source	`framework/db/Transaction.php`

1 subclass

yii\db\pgsql\Transaction

Transaction represents a DB transaction.

It is usually created by calling Connection::beginTransaction().

The following code is a typical example of using transactions (note that some DBMS may not support transactions):

$transaction = $connection->beginTransaction();
try {
    $connection->createCommand($sql1)->execute();
    $connection->createCommand($sql2)->execute();
    //.... other SQL executions
    $transaction->commit();
} catch (\Exception $e) {
    $transaction->rollBack();
    throw $e;
} catch (\Throwable $e) {
    $transaction->rollBack();
    throw $e;
}

Note: in the above code we have two catch-blocks for compatibility with PHP 5.x and PHP 7.x. \Exception implements the \Throwable interface since PHP 7.0, so you can skip the part with \Exception if your app uses only PHP 7.0 and higher.

Properties

Property	Type	Description	Defined by
`$db`	`Connection`	The database connection that this transaction is associated with. Default: `null`.	`Transaction`
`$isActive` read-only	`bool`	Whether this transaction is active.	`Transaction`
`$isolationLevel` write-only	`string`	The transaction isolation level to use for this transaction.	`Transaction`
`$level` read-only	`int`	The current nesting level of the transaction.	`Transaction`

Methods

Method	Description	Defined by
`__construct()`	Constructor.	`yii\base\BaseObject`
`__call()`	Calls the named method which is not a class method.	`yii\base\BaseObject`
`__get()`	Returns the value of an object property.	`yii\base\BaseObject`
`__isset()`	Checks if a property is set, i.e. defined and not null.	`yii\base\BaseObject`
`__set()`	Sets value of an object property.	`yii\base\BaseObject`
`__unset()`	Sets an object property to null.	`yii\base\BaseObject`
`begin()`	Begins a transaction.	`Transaction`
`canGetProperty()`	Returns a value indicating whether a property can be read.	`yii\base\BaseObject`
`canSetProperty()`	Returns a value indicating whether a property can be set.	`yii\base\BaseObject`
`className()` static	Returns the fully qualified name of this class.	`yii\base\BaseObject`
`commit()`	Commits a transaction.	`Transaction`
`getIsActive()`	Returns a value indicating whether this transaction is active.	`Transaction`
`getLevel()`		`Transaction`
`hasMethod()`	Returns a value indicating whether a method is defined.	`yii\base\BaseObject`
`hasProperty()`	Returns a value indicating whether a property is defined.	`yii\base\BaseObject`
`init()`	Initializes the object.	`yii\base\BaseObject`
`rollBack()`	Rolls back a transaction.	`Transaction`
`setIsolationLevel()`	Sets the transaction isolation level for this transaction.	`Transaction`

Constants

Constant	Value	Description	Defined by
`READ_UNCOMMITTED`	`'READ UNCOMMITTED'`	A constant representing the transaction isolation level `READ UNCOMMITTED`.	`Transaction`
`READ_COMMITTED`	`'READ COMMITTED'`	A constant representing the transaction isolation level `READ COMMITTED`.	`Transaction`
`REPEATABLE_READ`	`'REPEATABLE READ'`	A constant representing the transaction isolation level `REPEATABLE READ`.	`Transaction`
`SERIALIZABLE`	`'SERIALIZABLE'`	A constant representing the transaction isolation level `SERIALIZABLE`.	`Transaction`

Property details

$isActive

public bool $isActive

Whether this transaction is active.

Only an active transaction can commit() or rollBack().

Access

Read-only (virtual property).

$isolationLevel

public string $isolationLevel

The transaction isolation level to use for this transaction.

This can be one of READ_UNCOMMITTED, READ_COMMITTED, REPEATABLE_READ and SERIALIZABLE but also a string containing DBMS specific syntax to be used after SET TRANSACTION ISOLATION LEVEL.

Access

Write-only (virtual property).

Method details

begin()

public function begin(string|null $isolationLevel = null): mixed

Begins a transaction.

Parameters

Parameter	Type	Description
`$isolationLevel`	`string\|null`	The [isolation level][] to use for this transaction. This can be one of `READ_UNCOMMITTED`, `READ_COMMITTED`, `REPEATABLE_READ` and `SERIALIZABLE` but also a string containing DBMS specific syntax to be used after `SET TRANSACTION ISOLATION LEVEL`. If not specified (`null`) the isolation level will not be set explicitly and the DBMS default will be used. > Note: Some DBMS allow setting of the isolation level only for the whole connection so subsequent transactions may get the same isolation level even if you did not specify any. When using this feature you may need to set the isolation level for all transactions explicitly to avoid conflicting settings. At the time of this writing affected DBMS are MSSQL and SQLite. > Note: The isolation level applies to the outermost transaction only. Nested transactions are implemented with savepoints and always run at the isolation level of the outer transaction, so an `$isolationLevel` passed to a nested `begin()` call is ignored and a warning is logged (since 2.0.56). [isolation level]: https://en.wikipedia.org/wiki/Isolation_%28database_systems%29#Isolation_levels Starting from version 2.0.16, this method throws exception when beginning nested transaction and underlying DBMS does not support savepoints.

Returns

mixed

Throws

yii\base\InvalidConfigException: if $db is null
yii\base\NotSupportedException: if the DBMS does not support nested transactions
Exception: if DB connection fails

commit()

public function commit(): mixed

Commits a transaction.

Returns

mixed

Throws

Exception: if the transaction is not active

getIsActive()

public function getIsActive(): bool

Returns a value indicating whether this transaction is active.

Returns

bool: Whether this transaction is active. Only an active transaction can commit() or rollBack().

getLevel()

public function getLevel(): int

Returns

int: The current nesting level of the transaction.

Since

2.0.8

rollBack()

public function rollBack(): mixed

Rolls back a transaction.

Returns

mixed

setIsolationLevel()

public function setIsolationLevel(string $level): mixed

Sets the transaction isolation level for this transaction.

This method can be used to set the isolation level while the transaction is already active. However this is not supported by all DBMS so you might rather specify the isolation level directly when calling begin().

Parameters

Parameter	Type	Description
`$level`	`string`	The transaction isolation level to use for this transaction. This can be one of `READ_UNCOMMITTED`, `READ_COMMITTED`, `REPEATABLE_READ` and `SERIALIZABLE` but also a string containing DBMS specific syntax to be used after `SET TRANSACTION ISOLATION LEVEL`.

Returns

mixed

Throws

Exception: if the transaction is not active

See also

https://en.wikipedia.org/wiki/Isolation_%28database_systems%29#Isolation_levels