Reference documentation and code samples for the Cloud Spanner Client class Transaction.
Manages interaction with Cloud Spanner inside a Transaction.
Transactions can be started via Google\Cloud\Spanner\Database::runTransaction() (recommended) or via Google\Cloud\Spanner\Database::transaction(). Transactions should always call Google\Cloud\Spanner\Transaction::commit() or Google\Cloud\Spanner\Transaction::rollback() to ensure that locks are released in a timely manner.
If you do not plan on performing any writes in your transaction, a Google\Cloud\Spanner\Snapshot is a better solution which does not require a commit or rollback and does not lock any data.
Transactions may raise Google\Cloud\Core\Exception\AbortedException errors when the transaction cannot complete for any reason. In this case, the entire operation (all reads and writes) should be reapplied atomically. Google Cloud PHP handles this transparently when using Google\Cloud\Spanner\Database::runTransaction(). In other cases, it is highly recommended that applications implement their own retry logic.
Example:
use Google\Cloud\Spanner\SpannerClient;
$spanner = new SpannerClient();
$database = $spanner->connect('my-instance', 'my-database');
$database->runTransaction(function (Transaction $t) {
// do stuff.
$t->commit();
});
// Get a transaction to manage manually.
$transaction = $database->transaction();
Namespace
Google \ Cloud \ SpannerMethods
__construct
Parameters | |
---|---|
Name | Description |
operation |
Google\Cloud\Spanner\Operation
The Operation instance. |
session |
Google\Cloud\Spanner\Session\Session
The session to use for spanner interactions. |
transactionId |
string
[optional] The Transaction ID. If no ID is provided, the Transaction will be a Single-Use Transaction. |
isRetry |
bool
Whether the transaction will automatically retry or not. |
tag |
string
A transaction tag. Requests made using this transaction will use this as the transaction tag. |
options |
array
Configuration Options. |
↳ begin |
array
The begin Transaction options. Refer |
mapper |
Google\Cloud\Spanner\ValueMapper
Consumed internally for properly map mutation data. |
getCommitStats
Get the commit stats for this transaction. Commit stats are only available after commit has been called with
return_commit_stats
=> true. If commit is called multiple times, only the commitStats for the last commit will
be available.
Example:
$transaction->commit(["returnCommitStats" => true]);
$commitStats = $transaction->getCommitStats();
Returns | |
---|---|
Type | Description |
array |
The commit stats |
executeUpdate
See also:
Parameters | |
---|---|
Name | Description |
sql |
string
The query string to execute. |
options |
array
Configuration Options. |
↳ parameters |
array
A key/value array of Query Parameters, where the key is represented in the query string prefixed by a |
↳ types |
array
A key/value array of Query Parameter types. Generally, Google Cloud PHP can infer types. Explicit type declarations are required in the case of struct parameters, or when a null value exists as a parameter. Accepted values for primitive types are defined as constants on Google\Cloud\Spanner\Database, and are as follows: |
↳ requestOptions |
array
Request options. For more information on available options, please see the upstream documentation. Please note, if using the |
Returns | |
---|---|
Type | Description |
int |
The number of rows modified. |
executeUpdateBatch
See also:
Parameters | |
---|---|
Name | Description |
statements |
array[]
A list of DML statements to run. Each statement
must contain a |
options |
array
Configuration Options. |
↳ requestOptions |
array
Request options. For more information on available options, please see the upstream documentation. Please note, if using the |
Returns | |
---|---|
Type | Description |
Google\Cloud\Spanner\BatchDmlResult |
rollback
Roll back a transaction.
Rolls back a transaction, releasing any locks it holds. It is a good idea to call this for any transaction that includes one or more Read or ExecuteSql requests and ultimately decides not to commit.
This closes the transaction, preventing any future API calls inside it.
Rollback will NOT error if the transaction is not found or was already aborted.
Example:
$transaction->rollback();
Parameter | |
---|---|
Name | Description |
options |
array
[optional] Configuration Options. |
Returns | |
---|---|
Type | Description |
void |
commit
Commit and end the transaction.
It is advised that transactions be run inside Google\Cloud\Spanner\Database::runTransaction() in order to take advantage of automated transaction retry in case of a transaction aborted error.
Example:
$transaction->commit();
Parameters | |
---|---|
Name | Description |
options |
array
Configuration Options. |
↳ mutations |
array
An array of mutations to commit. May be used instead of or in addition to enqueing mutations separately. |
↳ returnCommitStats |
bool
If true, commit statistics will be returned and accessible via Google\Cloud\Spanner\Transaction::getCommitStats(). Defaults to |
↳ maxCommitDelay |
Duration
The amount of latency this request is willing to incur in order to improve throughput. Defaults to null. |
↳ requestOptions |
array
Request options. For more information on available options, please see the upstream documentation. Please note, if using the |
Returns | |
---|---|
Type | Description |
Google\Cloud\Spanner\Timestamp |
The commit timestamp. |
state
Retrieve the Transaction State.
Will be one of Transaction::STATE_ACTIVE
,
Transaction::STATE_COMMITTED
, or Transaction::STATE_ROLLED_BACK
.
Example:
$state = $transaction->state();
Returns | |
---|---|
Type | Description |
int |
isRetry
Check whether the current transaction is a retry transaction.
When using Google\Cloud\Spanner\Database::runTransaction(),
transactions are automatically retried when a conflict causes it to abort.
In such cases, subsequent invocations of the transaction callable will
provide a transaction where $transaction->isRetry()
is true. This can
be useful for debugging and understanding how code is working.
Example:
if ($transaction->isRetry()) {
echo 'This is a retry transaction!';
}
Returns | |
---|---|
Type | Description |
bool |