Reference documentation and code samples for the Cloud Spanner Client class ReadPartition.
Represents a Read Partition.
Partitions can be shared with other servers or processes by casting the object to a string, or by calling Google\Cloud\Spanner\Batch\Google\Cloud\Spanner\Batch\ReadPartition::serialize().
Note that when reading or querying against a partition, the request MUST be made using the same Batch Snapshot with which the partition was initialized. In practice, this means that a shared partition must be accompanied by its corresponding snapshot. For more information, refer to usage notes on Google\Cloud\Spanner\Batch\Google\Cloud\Spanner\Batch\BatchClient.
Example:
use Google\Cloud\Spanner\KeySet;
use Google\Cloud\Spanner\SpannerClient;
$spanner = new SpannerClient();
$batch = $spanner->batch('instance-id', 'database-id');
$snapshot = $batch->snapshot();
$keySet = new KeySet(['all' => true]);
$columns = ['id', 'firstName', 'lastName'];
$partitions = $snapshot->partitionRead('Users', $keySet, $columns);
// Serialize a partition to share it with another worker.
$partitionString = (string) $partition;
// Calling ReadPartition::serialize() has the same effect.
$partitionString = $partition->serialize();
Methods
__construct
| Parameters | |
|---|---|
| Name | Description |
token |
string
The token identifying the partition. |
table |
string
The table name. |
keySet |
Google\Cloud\Spanner\KeySet
The KeySet to select rows. |
columns |
string[]
A list of column names to return. |
options |
array
Configuration Options |
↳ maxPartitions |
int
The desired maximum number of partitions to return. For example, this may be set to the number of workers available. The maximum value is currently 200,000. This is only a hint. The actual number of partitions returned may be smaller than this maximum count request. Defaults to |
↳ partitionSizeBytes |
int
The desired data size for each partition generated. This is only a hint. The actual size of each partition may be smaller or larger than this size request. Defaults to |
↳ index |
string
The name of an index on the table. |
table
Return the table name.
Example:
$table = $partition->table();
| Returns | |
|---|---|
| Type | Description |
string | |
keySet
Return the KeySet.
Example:
$keySet = $partition->keySet();
| Returns | |
|---|---|
| Type | Description |
Google\Cloud\Spanner\KeySet | |
columns
Return the list of columns.
Example:
$columns = $partition->columns();
| Returns | |
|---|---|
| Type | Description |
array | |
serialize
Return a stringified representation of the ReadPartition object.
Example:
$partitionString = $partition->serialize();
| Returns | |
|---|---|
| Type | Description |
string | |
hydrate
Create a ReadPartition object from a deserialized array of partition data.
| Parameter | |
|---|---|
| Name | Description |
data |
array
The partition data. |
| Returns | |
|---|---|
| Type | Description |
Google\Cloud\Spanner\Batch\ReadPartition | |