The DirectedReadOptions can be used to indicate which replicas or regions should be used for non-transactional reads or queries.
DirectedReadOptions may only be specified for a read-only transaction, otherwise the API will return an INVALID_ARGUMENT
error.
JSON representation |
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{ // Union field |
Fields | |
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Union field replicas . Required. At most one of either include_replicas or exclude_replicas should be present in the message. replicas can be only one of the following: |
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include |
Include_replicas indicates the order of replicas (as they appear in this list) to process the request. If autoFailoverDisabled is set to true and all replicas are exhausted without finding a healthy replica, Spanner will wait for a replica in the list to become available, requests may fail due to |
exclude |
Exclude_replicas indicates that specified replicas should be excluded from serving requests. Spanner will not route requests to the replicas in this list. |
IncludeReplicas
An IncludeReplicas contains a repeated set of ReplicaSelection which indicates the order in which replicas should be considered.
JSON representation |
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{
"replicaSelections": [
{
object ( |
Fields | |
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replica |
The directed read replica selector. |
auto |
If true, Spanner will not route requests to a replica outside the includeReplicas list when all of the specified replicas are unavailable or unhealthy. Default value is |
ReplicaSelection
The directed read replica selector. Callers must provide one or more of the following fields for replica selection:
location
- The location must be one of the regions within the multi-region configuration of your database.type
- The type of the replica.
Some examples of using replica_selectors are:
location:us-east1
--> The "us-east1" replica(s) of any available type will be used to process the request.type:READ_ONLY
--> The "READ_ONLY" type replica(s) in nearest available location will be used to process the request.location:us-east1 type:READ_ONLY
--> The "READ_ONLY" type replica(s) in location "us-east1" will be used to process the request.
JSON representation |
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{
"location": string,
"type": enum ( |
Fields | |
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location |
The location or region of the serving requests, e.g. "us-east1". |
type |
The type of replica. |
Type
Indicates the type of replica.
Enums | |
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TYPE_UNSPECIFIED |
Not specified. |
READ_WRITE |
sessions.read-write replicas support both reads and writes. |
READ_ONLY |
sessions.read-only replicas only support reads (not writes). |
ExcludeReplicas
An ExcludeReplicas contains a repeated set of ReplicaSelection that should be excluded from serving requests.
JSON representation |
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{
"replicaSelections": [
{
object ( |
Fields | |
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replica |
The directed read replica selector. |