Cloud Spanner V1 Client - Class PBReadOnly (1.68.0)

Reference documentation and code samples for the Cloud Spanner V1 Client class PBReadOnly.

Message type to initiate a read-only transaction.

Generated from protobuf message google.spanner.v1.TransactionOptions.ReadOnly

Namespace

Google \ Cloud \ Spanner \ V1 \ TransactionOptions

Methods

__construct

Constructor.

Parameters
Name	Description
`data`	`array` Optional. Data for populating the Message object.
`↳ strong`	`bool` Read at a timestamp where all previously committed transactions are visible.
`↳ min_read_timestamp`	`Google\Protobuf\Timestamp` Executes all reads at a timestamp >= `min_read_timestamp`. This is useful for requesting fresher data than some previous read, or data that is fresh enough to observe the effects of some previously committed transaction whose timestamp is known. Note that this option can only be used in single-use transactions. A timestamp in RFC3339 UTC "Zulu" format, accurate to nanoseconds. Example: `"2014-10-02T15:01:23.045123456Z"`.
`↳ max_staleness`	`Google\Protobuf\Duration` Read data at a timestamp >= `NOW - max_staleness` seconds. Guarantees that all writes that have committed more than the specified number of seconds ago are visible. Because Cloud Spanner chooses the exact timestamp, this mode works even if the client's local clock is substantially skewed from Cloud Spanner commit timestamps. Useful for reading the freshest data available at a nearby replica, while bounding the possible staleness if the local replica has fallen behind. Note that this option can only be used in single-use transactions.
`↳ read_timestamp`	`Google\Protobuf\Timestamp` Executes all reads at the given timestamp. Unlike other modes, reads at a specific timestamp are repeatable; the same read at the same timestamp always returns the same data. If the timestamp is in the future, the read will block until the specified timestamp, modulo the read's deadline. Useful for large scale consistent reads such as mapreduces, or for coordinating many reads against a consistent snapshot of the data. A timestamp in RFC3339 UTC "Zulu" format, accurate to nanoseconds. Example: `"2014-10-02T15:01:23.045123456Z"`.
`↳ exact_staleness`	`Google\Protobuf\Duration` Executes all reads at a timestamp that is `exact_staleness` old. The timestamp is chosen soon after the read is started. Guarantees that all writes that have committed more than the specified number of seconds ago are visible. Because Cloud Spanner chooses the exact timestamp, this mode works even if the client's local clock is substantially skewed from Cloud Spanner commit timestamps. Useful for reading at nearby replicas without the distributed timestamp negotiation overhead of `max_staleness`.
`↳ return_read_timestamp`	`bool` If true, the Cloud Spanner-selected read timestamp is included in the Transaction message that describes the transaction.

getStrong

Read at a timestamp where all previously committed transactions are visible.

Returns
Type	Description
`bool`

hasStrong

setStrong

Read at a timestamp where all previously committed transactions are visible.

Parameter
Name	Description
`var`	`bool`

Returns
Type	Description
`$this`

getMinReadTimestamp

Executes all reads at a timestamp >= min_read_timestamp.

This is useful for requesting fresher data than some previous read, or data that is fresh enough to observe the effects of some previously committed transaction whose timestamp is known. Note that this option can only be used in single-use transactions. A timestamp in RFC3339 UTC "Zulu" format, accurate to nanoseconds. Example: "2014-10-02T15:01:23.045123456Z".

Returns
Type	Description
`Google\Protobuf\Timestamp\|null`

hasMinReadTimestamp

setMinReadTimestamp

Executes all reads at a timestamp >= min_read_timestamp.

Parameter
Name	Description
`var`	`Google\Protobuf\Timestamp`

Returns
Type	Description
`$this`

getMaxStaleness

Read data at a timestamp >= NOW - max_staleness seconds. Guarantees that all writes that have committed more than the specified number of seconds ago are visible. Because Cloud Spanner chooses the exact timestamp, this mode works even if the client's local clock is substantially skewed from Cloud Spanner commit timestamps.

Useful for reading the freshest data available at a nearby replica, while bounding the possible staleness if the local replica has fallen behind. Note that this option can only be used in single-use transactions.

Returns
Type	Description
`Google\Protobuf\Duration\|null`

hasMaxStaleness

setMaxStaleness

Parameter
Name	Description
`var`	`Google\Protobuf\Duration`

Returns
Type	Description
`$this`

getReadTimestamp

Executes all reads at the given timestamp. Unlike other modes, reads at a specific timestamp are repeatable; the same read at the same timestamp always returns the same data. If the timestamp is in the future, the read will block until the specified timestamp, modulo the read's deadline.

Useful for large scale consistent reads such as mapreduces, or for coordinating many reads against a consistent snapshot of the data. A timestamp in RFC3339 UTC "Zulu" format, accurate to nanoseconds. Example: "2014-10-02T15:01:23.045123456Z".

Returns
Type	Description
`Google\Protobuf\Timestamp\|null`

hasReadTimestamp

setReadTimestamp

Parameter
Name	Description
`var`	`Google\Protobuf\Timestamp`

Returns
Type	Description
`$this`

getExactStaleness

Executes all reads at a timestamp that is exact_staleness old. The timestamp is chosen soon after the read is started.

Guarantees that all writes that have committed more than the specified number of seconds ago are visible. Because Cloud Spanner chooses the exact timestamp, this mode works even if the client's local clock is substantially skewed from Cloud Spanner commit timestamps. Useful for reading at nearby replicas without the distributed timestamp negotiation overhead of max_staleness.

Returns
Type	Description
`Google\Protobuf\Duration\|null`

hasExactStaleness

setExactStaleness

Executes all reads at a timestamp that is exact_staleness old. The timestamp is chosen soon after the read is started.

Parameter
Name	Description
`var`	`Google\Protobuf\Duration`

Returns
Type	Description
`$this`

getReturnReadTimestamp

If true, the Cloud Spanner-selected read timestamp is included in the Transaction message that describes the transaction.

Returns
Type	Description
`bool`

setReturnReadTimestamp

If true, the Cloud Spanner-selected read timestamp is included in the Transaction message that describes the transaction.

Parameter
Name	Description
`var`	`bool`

Returns
Type	Description
`$this`

getTimestampBound

Returns
Type	Description
`string`