Cloud Spanner Client - Class ReadPartition (1.76.0)

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\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\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();

Namespace

Google \ Cloud \ Spanner \ Batch

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 `10000`.
`↳ 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 `1000000000` (i.e. 1 GiB).
`↳ 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`

static::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`