Types for Google Cloud Spanner v1 API¶
- class google.cloud.spanner_v1.types.BatchCreateSessionsRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [BatchCreateSessions][google.spanner.v1.Spanner.BatchCreateSessions].
- session_template¶
Parameters to be applied to each created session.
- session_count¶
Required. The number of sessions to be created in this batch call. The API may return fewer than the requested number of sessions. If a specific number of sessions are desired, the client can make additional calls to BatchCreateSessions (adjusting [session_count][google.spanner.v1.BatchCreateSessionsRequest.session_count] as necessary).
- Type
- class google.cloud.spanner_v1.types.BatchCreateSessionsResponse(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe response for [BatchCreateSessions][google.spanner.v1.Spanner.BatchCreateSessions].
- session¶
The freshly created sessions.
- Type
MutableSequence[google.cloud.spanner_v1.types.Session]
- class google.cloud.spanner_v1.types.BatchWriteRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [BatchWrite][google.spanner.v1.Spanner.BatchWrite].
- request_options¶
Common options for this request.
- mutation_groups¶
Required. The groups of mutations to be applied.
- Type
MutableSequence[google.cloud.spanner_v1.types.BatchWriteRequest.MutationGroup]
- exclude_txn_from_change_streams¶
Optional. When
exclude_txn_from_change_streamsis set totrue:Mutations from all transactions in this batch write operation will not be recorded in change streams with DDL option
allow_txn_exclusion=truethat are tracking columns modified by these transactions.Mutations from all transactions in this batch write operation will be recorded in change streams with DDL option
allow_txn_exclusion=false or not setthat are tracking columns modified by these transactions.
When
exclude_txn_from_change_streamsis set tofalseor not set, mutations from all transactions in this batch write operation will be recorded in all change streams that are tracking columns modified by these transactions.- Type
- class MutationGroup(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageA group of mutations to be committed together. Related mutations should be placed in a group. For example, two mutations inserting rows with the same primary key prefix in both parent and child tables are related.
- mutations¶
Required. The mutations in this group.
- Type
MutableSequence[google.cloud.spanner_v1.types.Mutation]
- class google.cloud.spanner_v1.types.BatchWriteResponse(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe result of applying a batch of mutations.
- indexes¶
The mutation groups applied in this batch. The values index into the
mutation_groupsfield in the correspondingBatchWriteRequest.- Type
MutableSequence[int]
- status¶
An
OKstatus indicates success. Any other status indicates a failure.- Type
google.rpc.status_pb2.Status
- commit_timestamp¶
The commit timestamp of the transaction that applied this batch. Present if
statusisOK, absent otherwise.
- class google.cloud.spanner_v1.types.BeginTransactionRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [BeginTransaction][google.spanner.v1.Spanner.BeginTransaction].
- options¶
Required. Options for the new transaction.
- request_options¶
Common options for this request. Priority is ignored for this request. Setting the priority in this request_options struct will not do anything. To set the priority for a transaction, set it on the reads and writes that are part of this transaction instead.
- mutation_key¶
Optional. Required for read-write transactions on a multiplexed session that commit mutations but do not perform any reads or queries. Clients should randomly select one of the mutations from the mutation set and send it as a part of this request. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- class google.cloud.spanner_v1.types.CommitRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [Commit][google.spanner.v1.Spanner.Commit].
This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- transaction_id¶
Commit a previously-started transaction.
This field is a member of oneof
transaction.- Type
- single_use_transaction¶
Execute mutations in a temporary transaction. Note that unlike commit of a previously-started transaction, commit with a temporary transaction is non-idempotent. That is, if the
CommitRequestis sent to Cloud Spanner more than once (for instance, due to retries in the application, or in the transport library), it is possible that the mutations are executed more than once. If this is undesirable, use [BeginTransaction][google.spanner.v1.Spanner.BeginTransaction] and [Commit][google.spanner.v1.Spanner.Commit] instead.This field is a member of oneof
transaction.
- mutations¶
The mutations to be executed when this transaction commits. All mutations are applied atomically, in the order they appear in this list.
- Type
MutableSequence[google.cloud.spanner_v1.types.Mutation]
- return_commit_stats¶
If
true, then statistics related to the transaction will be included in the [CommitResponse][google.spanner.v1.CommitResponse.commit_stats]. Default value isfalse.- Type
- max_commit_delay¶
Optional. The amount of latency this request is willing to incur in order to improve throughput. If this field is not set, Spanner assumes requests are relatively latency sensitive and automatically determines an appropriate delay time. You can specify a batching delay value between 0 and 500 ms.
- request_options¶
Common options for this request.
- precommit_token¶
Optional. If the read-write transaction was executed on a multiplexed session, the precommit token with the highest sequence number received in this transaction attempt, should be included here. Failing to do so will result in a FailedPrecondition error. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- class google.cloud.spanner_v1.types.CommitResponse(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe response for [Commit][google.spanner.v1.Spanner.Commit].
- commit_timestamp¶
The Cloud Spanner timestamp at which the transaction committed.
- commit_stats¶
The statistics about this Commit. Not returned by default. For more information, see [CommitRequest.return_commit_stats][google.spanner.v1.CommitRequest.return_commit_stats].
- precommit_token¶
If specified, transaction has not committed yet. Clients must retry the commit with the new precommit token.
This field is a member of oneof
MultiplexedSessionRetry.
- class CommitStats(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageAdditional statistics about a commit.
- mutation_count¶
The total number of mutations for the transaction. Knowing the
mutation_countvalue can help you maximize the number of mutations in a transaction and minimize the number of API round trips. You can also monitor this value to prevent transactions from exceeding the system limit. If the number of mutations exceeds the limit, the server returns INVALID_ARGUMENT.- Type
- class google.cloud.spanner_v1.types.CreateSessionRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [CreateSession][google.spanner.v1.Spanner.CreateSession].
- session¶
Required. The session to create.
- class google.cloud.spanner_v1.types.DeleteSessionRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [DeleteSession][google.spanner.v1.Spanner.DeleteSession].
- class google.cloud.spanner_v1.types.DirectedReadOptions(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe 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_ARGUMENTerror.This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- include_replicas¶
Include_replicas indicates the order of replicas (as they appear in this list) to process the request. If auto_failover_disabled 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
DEADLINE_EXCEEDEDerrors.This field is a member of oneof
replicas.
- exclude_replicas¶
Exclude_replicas indicates that specified replicas should be excluded from serving requests. Spanner will not route requests to the replicas in this list.
This field is a member of oneof
replicas.
- class ExcludeReplicas(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageAn ExcludeReplicas contains a repeated set of ReplicaSelection that should be excluded from serving requests.
- replica_selections¶
The directed read replica selector.
- Type
MutableSequence[google.cloud.spanner_v1.types.DirectedReadOptions.ReplicaSelection]
- class IncludeReplicas(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageAn IncludeReplicas contains a repeated set of ReplicaSelection which indicates the order in which replicas should be considered.
- replica_selections¶
The directed read replica selector.
- Type
MutableSequence[google.cloud.spanner_v1.types.DirectedReadOptions.ReplicaSelection]
- class ReplicaSelection(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe 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.
- type_¶
The type of replica.
- class Type(value)[source]¶
Bases:
proto.enums.EnumIndicates the type of replica.
- Values:
- TYPE_UNSPECIFIED (0):
Not specified.
- READ_WRITE (1):
Read-write replicas support both reads and writes.
- READ_ONLY (2):
Read-only replicas only support reads (not writes).
- class google.cloud.spanner_v1.types.ExecuteBatchDmlRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [ExecuteBatchDml][google.spanner.v1.Spanner.ExecuteBatchDml].
- transaction¶
Required. The transaction to use. Must be a read-write transaction. To protect against replays, single-use transactions are not supported. The caller must either supply an existing transaction ID or begin a new transaction.
- statements¶
Required. The list of statements to execute in this batch. Statements are executed serially, such that the effects of statement
iare visible to statementi+1. Each statement must be a DML statement. Execution stops at the first failed statement; the remaining statements are not executed.Callers must provide at least one statement.
- Type
MutableSequence[google.cloud.spanner_v1.types.ExecuteBatchDmlRequest.Statement]
- seqno¶
Required. A per-transaction sequence number used to identify this request. This field makes each request idempotent such that if the request is received multiple times, at most one will succeed.
The sequence number must be monotonically increasing within the transaction. If a request arrives for the first time with an out-of-order sequence number, the transaction may be aborted. Replays of previously handled requests will yield the same response as the first execution.
- Type
- request_options¶
Common options for this request.
- class Statement(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageA single DML statement.
- params¶
Parameter names and values that bind to placeholders in the DML string.
A parameter placeholder consists of the
@character followed by the parameter name (for example,@firstName). Parameter names can contain letters, numbers, and underscores.Parameters can appear anywhere that a literal value is expected. The same parameter name can be used more than once, for example:
"WHERE id > @msg_id AND id < @msg_id + 100"It is an error to execute a SQL statement with unbound parameters.
- param_types¶
It is not always possible for Cloud Spanner to infer the right SQL type from a JSON value. For example, values of type
BYTESand values of typeSTRINGboth appear in [params][google.spanner.v1.ExecuteBatchDmlRequest.Statement.params] as JSON strings.In these cases,
param_typescan be used to specify the exact SQL type for some or all of the SQL statement parameters. See the definition of [Type][google.spanner.v1.Type] for more information about SQL types.- Type
MutableMapping[str, google.cloud.spanner_v1.types.Type]
- class ParamTypesEntry(mapping=None, *, ignore_unknown_fields=False, **kwargs)¶
Bases:
proto.message.Message
- class google.cloud.spanner_v1.types.ExecuteBatchDmlResponse(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe response for [ExecuteBatchDml][google.spanner.v1.Spanner.ExecuteBatchDml]. Contains a list of [ResultSet][google.spanner.v1.ResultSet] messages, one for each DML statement that has successfully executed, in the same order as the statements in the request. If a statement fails, the status in the response body identifies the cause of the failure.
To check for DML statements that failed, use the following approach:
Check the status in the response message. The [google.rpc.Code][google.rpc.Code] enum value
OKindicates that all statements were executed successfully.If the status was not
OK, check the number of result sets in the response. If the response containsN[ResultSet][google.spanner.v1.ResultSet] messages, then statementN+1in the request failed.
Example 1:
Request: 5 DML statements, all executed successfully.
Response: 5 [ResultSet][google.spanner.v1.ResultSet] messages, with the status
OK.
Example 2:
Request: 5 DML statements. The third statement has a syntax error.
Response: 2 [ResultSet][google.spanner.v1.ResultSet] messages, and a syntax error (
INVALID_ARGUMENT) status. The number of [ResultSet][google.spanner.v1.ResultSet] messages indicates that the third statement failed, and the fourth and fifth statements were not executed.
- result_sets¶
One [ResultSet][google.spanner.v1.ResultSet] for each statement in the request that ran successfully, in the same order as the statements in the request. Each [ResultSet][google.spanner.v1.ResultSet] does not contain any rows. The [ResultSetStats][google.spanner.v1.ResultSetStats] in each [ResultSet][google.spanner.v1.ResultSet] contain the number of rows modified by the statement.
Only the first [ResultSet][google.spanner.v1.ResultSet] in the response contains valid [ResultSetMetadata][google.spanner.v1.ResultSetMetadata].
- Type
MutableSequence[google.cloud.spanner_v1.types.ResultSet]
- status¶
If all DML statements are executed successfully, the status is
OK. Otherwise, the error status of the first failed statement.- Type
google.rpc.status_pb2.Status
- precommit_token¶
Optional. A precommit token will be included if the read-write transaction is on a multiplexed session. The precommit token with the highest sequence number from this transaction attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit] request for this transaction. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- class google.cloud.spanner_v1.types.ExecuteSqlRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql] and [ExecuteStreamingSql][google.spanner.v1.Spanner.ExecuteStreamingSql].
- transaction¶
The transaction to use.
For queries, if none is provided, the default is a temporary read-only transaction with strong concurrency.
Standard DML statements require a read-write transaction. To protect against replays, single-use transactions are not supported. The caller must either supply an existing transaction ID or begin a new transaction.
Partitioned DML requires an existing Partitioned DML transaction ID.
- params¶
Parameter names and values that bind to placeholders in the SQL string.
A parameter placeholder consists of the
@character followed by the parameter name (for example,@firstName). Parameter names must conform to the naming requirements of identifiers as specified at https://cloud.google.com/spanner/docs/lexical#identifiers.Parameters can appear anywhere that a literal value is expected. The same parameter name can be used more than once, for example:
"WHERE id > @msg_id AND id < @msg_id + 100"It is an error to execute a SQL statement with unbound parameters.
- param_types¶
It is not always possible for Cloud Spanner to infer the right SQL type from a JSON value. For example, values of type
BYTESand values of typeSTRINGboth appear in [params][google.spanner.v1.ExecuteSqlRequest.params] as JSON strings.In these cases,
param_typescan be used to specify the exact SQL type for some or all of the SQL statement parameters. See the definition of [Type][google.spanner.v1.Type] for more information about SQL types.- Type
MutableMapping[str, google.cloud.spanner_v1.types.Type]
- resume_token¶
If this request is resuming a previously interrupted SQL statement execution,
resume_tokenshould be copied from the last [PartialResultSet][google.spanner.v1.PartialResultSet] yielded before the interruption. Doing this enables the new SQL statement execution to resume where the last one left off. The rest of the request parameters must exactly match the request that yielded this token.- Type
- query_mode¶
Used to control the amount of debugging information returned in [ResultSetStats][google.spanner.v1.ResultSetStats]. If [partition_token][google.spanner.v1.ExecuteSqlRequest.partition_token] is set, [query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode] can only be set to [QueryMode.NORMAL][google.spanner.v1.ExecuteSqlRequest.QueryMode.NORMAL].
- partition_token¶
If present, results will be restricted to the specified partition previously created using PartitionQuery(). There must be an exact match for the values of fields common to this message and the PartitionQueryRequest message used to create this partition_token.
- Type
- seqno¶
A per-transaction sequence number used to identify this request. This field makes each request idempotent such that if the request is received multiple times, at most one will succeed.
The sequence number must be monotonically increasing within the transaction. If a request arrives for the first time with an out-of-order sequence number, the transaction may be aborted. Replays of previously handled requests will yield the same response as the first execution.
Required for DML statements. Ignored for queries.
- Type
- query_options¶
Query optimizer configuration to use for the given query.
- request_options¶
Common options for this request.
- directed_read_options¶
Directed read options for this request.
- data_boost_enabled¶
If this is for a partitioned query and this field is set to
true, the request is executed with Spanner Data Boost independent compute resources.If the field is set to
truebut the request does not setpartition_token, the API returns anINVALID_ARGUMENTerror.- Type
- class ParamTypesEntry(mapping=None, *, ignore_unknown_fields=False, **kwargs)¶
Bases:
proto.message.Message
- class QueryMode(value)[source]¶
Bases:
proto.enums.EnumMode in which the statement must be processed.
- Values:
- NORMAL (0):
The default mode. Only the statement results are returned.
- PLAN (1):
This mode returns only the query plan, without any results or execution statistics information.
- PROFILE (2):
This mode returns the query plan, overall execution statistics, operator level execution statistics along with the results. This has a performance overhead compared to the other modes. It is not recommended to use this mode for production traffic.
- WITH_STATS (3):
This mode returns the overall (but not operator-level) execution statistics along with the results.
- WITH_PLAN_AND_STATS (4):
This mode returns the query plan, overall (but not operator-level) execution statistics along with the results.
- class QueryOptions(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageQuery optimizer configuration.
- optimizer_version¶
An option to control the selection of optimizer version.
This parameter allows individual queries to pick different query optimizer versions.
Specifying
latestas a value instructs Cloud Spanner to use the latest supported query optimizer version. If not specified, Cloud Spanner uses the optimizer version set at the database level options. Any other positive integer (from the list of supported optimizer versions) overrides the default optimizer version for query execution.The list of supported optimizer versions can be queried from SPANNER_SYS.SUPPORTED_OPTIMIZER_VERSIONS.
Executing a SQL statement with an invalid optimizer version fails with an
INVALID_ARGUMENTerror.See https://cloud.google.com/spanner/docs/query-optimizer/manage-query-optimizer for more information on managing the query optimizer.
The
optimizer_versionstatement hint has precedence over this setting.- Type
- optimizer_statistics_package¶
An option to control the selection of optimizer statistics package.
This parameter allows individual queries to use a different query optimizer statistics package.
Specifying
latestas a value instructs Cloud Spanner to use the latest generated statistics package. If not specified, Cloud Spanner uses the statistics package set at the database level options, or the latest package if the database option is not set.The statistics package requested by the query has to be exempt from garbage collection. This can be achieved with the following DDL statement:
ALTER STATISTICS <package_name> SET OPTIONS (allow_gc=false)
The list of available statistics packages can be queried from
INFORMATION_SCHEMA.SPANNER_STATISTICS.Executing a SQL statement with an invalid optimizer statistics package or with a statistics package that allows garbage collection fails with an
INVALID_ARGUMENTerror.- Type
- class google.cloud.spanner_v1.types.GetSessionRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [GetSession][google.spanner.v1.Spanner.GetSession].
- class google.cloud.spanner_v1.types.KeyRange(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageKeyRange represents a range of rows in a table or index.
A range has a start key and an end key. These keys can be open or closed, indicating if the range includes rows with that key.
Keys are represented by lists, where the ith value in the list corresponds to the ith component of the table or index primary key. Individual values are encoded as described [here][google.spanner.v1.TypeCode].
For example, consider the following table definition:
CREATE TABLE UserEvents ( UserName STRING(MAX), EventDate STRING(10) ) PRIMARY KEY(UserName, EventDate);
The following keys name rows in this table:
["Bob", "2014-09-23"] ["Alfred", "2015-06-12"]
Since the
UserEventstable’sPRIMARY KEYclause names two columns, eachUserEventskey has two elements; the first is theUserName, and the second is theEventDate.Key ranges with multiple components are interpreted lexicographically by component using the table or index key’s declared sort order. For example, the following range returns all events for user
"Bob"that occurred in the year 2015:"start_closed": ["Bob", "2015-01-01"] "end_closed": ["Bob", "2015-12-31"]
Start and end keys can omit trailing key components. This affects the inclusion and exclusion of rows that exactly match the provided key components: if the key is closed, then rows that exactly match the provided components are included; if the key is open, then rows that exactly match are not included.
For example, the following range includes all events for
"Bob"that occurred during and after the year 2000:"start_closed": ["Bob", "2000-01-01"] "end_closed": ["Bob"]
The next example retrieves all events for
"Bob":"start_closed": ["Bob"] "end_closed": ["Bob"]
To retrieve events before the year 2000:
"start_closed": ["Bob"] "end_open": ["Bob", "2000-01-01"]
The following range includes all rows in the table:
"start_closed": [] "end_closed": []
This range returns all users whose
UserNamebegins with any character from A to C:"start_closed": ["A"] "end_open": ["D"]
This range returns all users whose
UserNamebegins with B:"start_closed": ["B"] "end_open": ["C"]
Key ranges honor column sort order. For example, suppose a table is defined as follows:
CREATE TABLE DescendingSortedTable { Key INT64, ... ) PRIMARY KEY(Key DESC);
The following range retrieves all rows with key values between 1 and 100 inclusive:
"start_closed": ["100"] "end_closed": ["1"]
Note that 100 is passed as the start, and 1 is passed as the end, because
Keyis a descending column in the schema.This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- start_closed¶
If the start is closed, then the range includes all rows whose first
len(start_closed)key columns exactly matchstart_closed.This field is a member of oneof
start_key_type.
- start_open¶
If the start is open, then the range excludes rows whose first
len(start_open)key columns exactly matchstart_open.This field is a member of oneof
start_key_type.
- end_closed¶
If the end is closed, then the range includes all rows whose first
len(end_closed)key columns exactly matchend_closed.This field is a member of oneof
end_key_type.
- class google.cloud.spanner_v1.types.KeySet(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageKeySetdefines a collection of Cloud Spanner keys and/or key ranges. All the keys are expected to be in the same table or index. The keys need not be sorted in any particular way.If the same key is specified multiple times in the set (for example if two ranges, two keys, or a key and a range overlap), Cloud Spanner behaves as if the key were only specified once.
- keys¶
A list of specific keys. Entries in
keysshould have exactly as many elements as there are columns in the primary or index key with which thisKeySetis used. Individual key values are encoded as described [here][google.spanner.v1.TypeCode].- Type
MutableSequence[google.protobuf.struct_pb2.ListValue]
- ranges¶
A list of key ranges. See [KeyRange][google.spanner.v1.KeyRange] for more information about key range specifications.
- Type
MutableSequence[google.cloud.spanner_v1.types.KeyRange]
- class google.cloud.spanner_v1.types.ListSessionsRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [ListSessions][google.spanner.v1.Spanner.ListSessions].
- page_size¶
Number of sessions to be returned in the response. If 0 or less, defaults to the server’s maximum allowed page size.
- Type
- page_token¶
If non-empty,
page_tokenshould contain a [next_page_token][google.spanner.v1.ListSessionsResponse.next_page_token] from a previous [ListSessionsResponse][google.spanner.v1.ListSessionsResponse].- Type
- filter¶
An expression for filtering the results of the request. Filter rules are case insensitive. The fields eligible for filtering are:
labels.keywhere key is the name of a label
Some examples of using filters are:
labels.env:*–> The session has the label “env”.labels.env:dev–> The session has the label “env” and the value of the label contains the string “dev”.
- Type
- class google.cloud.spanner_v1.types.ListSessionsResponse(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe response for [ListSessions][google.spanner.v1.Spanner.ListSessions].
- sessions¶
The list of requested sessions.
- Type
MutableSequence[google.cloud.spanner_v1.types.Session]
- class google.cloud.spanner_v1.types.MultiplexedSessionPrecommitToken(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageWhen a read-write transaction is executed on a multiplexed session, this precommit token is sent back to the client as a part of the [Transaction] message in the BeginTransaction response and also as a part of the [ResultSet] and [PartialResultSet] responses.
- class google.cloud.spanner_v1.types.Mutation(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageA modification to one or more Cloud Spanner rows. Mutations can be applied to a Cloud Spanner database by sending them in a [Commit][google.spanner.v1.Spanner.Commit] call.
This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- insert¶
Insert new rows in a table. If any of the rows already exist, the write or transaction fails with error
ALREADY_EXISTS.This field is a member of oneof
operation.
- update¶
Update existing rows in a table. If any of the rows does not already exist, the transaction fails with error
NOT_FOUND.This field is a member of oneof
operation.
- insert_or_update¶
Like [insert][google.spanner.v1.Mutation.insert], except that if the row already exists, then its column values are overwritten with the ones provided. Any column values not explicitly written are preserved.
When using [insert_or_update][google.spanner.v1.Mutation.insert_or_update], just as when using [insert][google.spanner.v1.Mutation.insert], all
NOT NULLcolumns in the table must be given a value. This holds true even when the row already exists and will therefore actually be updated.This field is a member of oneof
operation.
- replace¶
Like [insert][google.spanner.v1.Mutation.insert], except that if the row already exists, it is deleted, and the column values provided are inserted instead. Unlike [insert_or_update][google.spanner.v1.Mutation.insert_or_update], this means any values not explicitly written become
NULL.In an interleaved table, if you create the child table with the
ON DELETE CASCADEannotation, then replacing a parent row also deletes the child rows. Otherwise, you must delete the child rows before you replace the parent row.This field is a member of oneof
operation.
- delete¶
Delete rows from a table. Succeeds whether or not the named rows were present.
This field is a member of oneof
operation.
- class Delete(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageArguments to [delete][google.spanner.v1.Mutation.delete] operations.
- key_set¶
Required. The primary keys of the rows within [table][google.spanner.v1.Mutation.Delete.table] to delete. The primary keys must be specified in the order in which they appear in the
PRIMARY KEY()clause of the table’s equivalent DDL statement (the DDL statement used to create the table). Delete is idempotent. The transaction will succeed even if some or all rows do not exist.
- class Write(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageArguments to [insert][google.spanner.v1.Mutation.insert], [update][google.spanner.v1.Mutation.update], [insert_or_update][google.spanner.v1.Mutation.insert_or_update], and [replace][google.spanner.v1.Mutation.replace] operations.
- columns¶
The names of the columns in [table][google.spanner.v1.Mutation.Write.table] to be written.
The list of columns must contain enough columns to allow Cloud Spanner to derive values for all primary key columns in the row(s) to be modified.
- Type
MutableSequence[str]
- values¶
The values to be written.
valuescan contain more than one list of values. If it does, then multiple rows are written, one for each entry invalues. Each list invaluesmust have exactly as many entries as there are entries in [columns][google.spanner.v1.Mutation.Write.columns] above. Sending multiple lists is equivalent to sending multipleMutations, each containing onevaluesentry and repeating [table][google.spanner.v1.Mutation.Write.table] and [columns][google.spanner.v1.Mutation.Write.columns]. Individual values in each list are encoded as described [here][google.spanner.v1.TypeCode].- Type
MutableSequence[google.protobuf.struct_pb2.ListValue]
- class google.cloud.spanner_v1.types.PartialResultSet(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessagePartial results from a streaming read or SQL query. Streaming reads and SQL queries better tolerate large result sets, large rows, and large values, but are a little trickier to consume.
- metadata¶
Metadata about the result set, such as row type information. Only present in the first response.
- values¶
A streamed result set consists of a stream of values, which might be split into many
PartialResultSetmessages to accommodate large rows and/or large values. Every N complete values defines a row, where N is equal to the number of entries in [metadata.row_type.fields][google.spanner.v1.StructType.fields].Most values are encoded based on type as described [here][google.spanner.v1.TypeCode].
It is possible that the last value in values is “chunked”, meaning that the rest of the value is sent in subsequent
PartialResultSet(s). This is denoted by the [chunked_value][google.spanner.v1.PartialResultSet.chunked_value] field. Two or more chunked values can be merged to form a complete value as follows:bool/number/null: cannot be chunkedstring: concatenate the stringslist: concatenate the lists. If the last element in a list is astring,list, orobject, merge it with the first element in the next list by applying these rules recursively.object: concatenate the (field name, field value) pairs. If a field name is duplicated, then apply these rules recursively to merge the field values.
Some examples of merging:
# Strings are concatenated. "foo", "bar" => "foobar" # Lists of non-strings are concatenated. [2, 3], [4] => [2, 3, 4] # Lists are concatenated, but the last and first elements are merged # because they are strings. ["a", "b"], ["c", "d"] => ["a", "bc", "d"] # Lists are concatenated, but the last and first elements are merged # because they are lists. Recursively, the last and first elements # of the inner lists are merged because they are strings. ["a", ["b", "c"]], [["d"], "e"] => ["a", ["b", "cd"], "e"] # Non-overlapping object fields are combined. {"a": "1"}, {"b": "2"} => {"a": "1", "b": 2"} # Overlapping object fields are merged. {"a": "1"}, {"a": "2"} => {"a": "12"} # Examples of merging objects containing lists of strings. {"a": ["1"]}, {"a": ["2"]} => {"a": ["12"]}
For a more complete example, suppose a streaming SQL query is yielding a result set whose rows contain a single string field. The following
PartialResultSets might be yielded:{ "metadata": { ... } "values": ["Hello", "W"] "chunked_value": true "resume_token": "Af65..." } { "values": ["orl"] "chunked_value": true "resume_token": "Bqp2..." } { "values": ["d"] "resume_token": "Zx1B..." }
This sequence of
PartialResultSets encodes two rows, one containing the field value"Hello", and a second containing the field value"World" = "W" + "orl" + "d".- Type
MutableSequence[google.protobuf.struct_pb2.Value]
- chunked_value¶
If true, then the final value in [values][google.spanner.v1.PartialResultSet.values] is chunked, and must be combined with more values from subsequent
PartialResultSets to obtain a complete field value.- Type
- resume_token¶
Streaming calls might be interrupted for a variety of reasons, such as TCP connection loss. If this occurs, the stream of results can be resumed by re-sending the original request and including
resume_token. Note that executing any other transaction in the same session invalidates the token.- Type
- stats¶
Query plan and execution statistics for the statement that produced this streaming result set. These can be requested by setting [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode] and are sent only once with the last response in the stream. This field will also be present in the last response for DML statements.
- precommit_token¶
Optional. A precommit token will be included if the read-write transaction is on a multiplexed session. The precommit token with the highest sequence number from this transaction attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit] request for this transaction. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- class google.cloud.spanner_v1.types.Partition(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageInformation returned for each partition returned in a PartitionResponse.
- class google.cloud.spanner_v1.types.PartitionOptions(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageOptions for a PartitionQueryRequest and PartitionReadRequest.
- partition_size_bytes¶
Note: This hint is currently ignored by PartitionQuery and PartitionRead requests.
The desired data size for each partition generated. The default for this option is currently 1 GiB. This is only a hint. The actual size of each partition may be smaller or larger than this size request.
- Type
- max_partitions¶
Note: This hint is currently ignored by PartitionQuery and PartitionRead requests.
The desired maximum number of partitions to return. For example, this may be set to the number of workers available. The default for this option is currently 10,000. The maximum value is currently 200,000. This is only a hint. The actual number of partitions returned may be smaller or larger than this maximum count request.
- Type
- class google.cloud.spanner_v1.types.PartitionQueryRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [PartitionQuery][google.spanner.v1.Spanner.PartitionQuery]
- transaction¶
Read only snapshot transactions are supported, read/write and single use transactions are not.
- sql¶
Required. The query request to generate partitions for. The request will fail if the query is not root partitionable. For a query to be root partitionable, it needs to satisfy a few conditions. For example, if the query execution plan contains a distributed union operator, then it must be the first operator in the plan. For more information about other conditions, see Read data in parallel.
The query request must not contain DML commands, such as INSERT, UPDATE, or DELETE. Use [ExecuteStreamingSql][google.spanner.v1.Spanner.ExecuteStreamingSql] with a PartitionedDml transaction for large, partition-friendly DML operations.
- Type
- params¶
Parameter names and values that bind to placeholders in the SQL string.
A parameter placeholder consists of the
@character followed by the parameter name (for example,@firstName). Parameter names can contain letters, numbers, and underscores.Parameters can appear anywhere that a literal value is expected. The same parameter name can be used more than once, for example:
"WHERE id > @msg_id AND id < @msg_id + 100"It is an error to execute a SQL statement with unbound parameters.
- param_types¶
It is not always possible for Cloud Spanner to infer the right SQL type from a JSON value. For example, values of type
BYTESand values of typeSTRINGboth appear in [params][google.spanner.v1.PartitionQueryRequest.params] as JSON strings.In these cases,
param_typescan be used to specify the exact SQL type for some or all of the SQL query parameters. See the definition of [Type][google.spanner.v1.Type] for more information about SQL types.- Type
MutableMapping[str, google.cloud.spanner_v1.types.Type]
- partition_options¶
Additional options that affect how many partitions are created.
- class ParamTypesEntry(mapping=None, *, ignore_unknown_fields=False, **kwargs)¶
Bases:
proto.message.Message
- class google.cloud.spanner_v1.types.PartitionReadRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [PartitionRead][google.spanner.v1.Spanner.PartitionRead]
- transaction¶
Read only snapshot transactions are supported, read/write and single use transactions are not.
- index¶
If non-empty, the name of an index on [table][google.spanner.v1.PartitionReadRequest.table]. This index is used instead of the table primary key when interpreting [key_set][google.spanner.v1.PartitionReadRequest.key_set] and sorting result rows. See [key_set][google.spanner.v1.PartitionReadRequest.key_set] for further information.
- Type
- columns¶
The columns of [table][google.spanner.v1.PartitionReadRequest.table] to be returned for each row matching this request.
- Type
MutableSequence[str]
- key_set¶
Required.
key_setidentifies the rows to be yielded.key_setnames the primary keys of the rows in [table][google.spanner.v1.PartitionReadRequest.table] to be yielded, unless [index][google.spanner.v1.PartitionReadRequest.index] is present. If [index][google.spanner.v1.PartitionReadRequest.index] is present, then [key_set][google.spanner.v1.PartitionReadRequest.key_set] instead names index keys in [index][google.spanner.v1.PartitionReadRequest.index].It is not an error for the
key_setto name rows that do not exist in the database. Read yields nothing for nonexistent rows.
- partition_options¶
Additional options that affect how many partitions are created.
- class google.cloud.spanner_v1.types.PartitionResponse(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe response for [PartitionQuery][google.spanner.v1.Spanner.PartitionQuery] or [PartitionRead][google.spanner.v1.Spanner.PartitionRead]
- partitions¶
Partitions created by this request.
- Type
MutableSequence[google.cloud.spanner_v1.types.Partition]
- transaction¶
Transaction created by this request.
- class google.cloud.spanner_v1.types.PlanNode(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageNode information for nodes appearing in a [QueryPlan.plan_nodes][google.spanner.v1.QueryPlan.plan_nodes].
- kind¶
Used to determine the type of node. May be needed for visualizing different kinds of nodes differently. For example, If the node is a [SCALAR][google.spanner.v1.PlanNode.Kind.SCALAR] node, it will have a condensed representation which can be used to directly embed a description of the node in its parent.
- child_links¶
List of child node
indexes and their relationship to this parent.- Type
MutableSequence[google.cloud.spanner_v1.types.PlanNode.ChildLink]
- short_representation¶
Condensed representation for [SCALAR][google.spanner.v1.PlanNode.Kind.SCALAR] nodes.
- metadata¶
Attributes relevant to the node contained in a group of key-value pairs. For example, a Parameter Reference node could have the following information in its metadata:
{ "parameter_reference": "param1", "parameter_type": "array" }
- execution_stats¶
The execution statistics associated with the node, contained in a group of key-value pairs. Only present if the plan was returned as a result of a profile query. For example, number of executions, number of rows/time per execution etc.
- class ChildLink(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageMetadata associated with a parent-child relationship appearing in a [PlanNode][google.spanner.v1.PlanNode].
- type_¶
The type of the link. For example, in Hash Joins this could be used to distinguish between the build child and the probe child, or in the case of the child being an output variable, to represent the tag associated with the output variable.
- Type
- variable¶
Only present if the child node is [SCALAR][google.spanner.v1.PlanNode.Kind.SCALAR] and corresponds to an output variable of the parent node. The field carries the name of the output variable. For example, a
TableScanoperator that reads rows from a table will have child links to theSCALARnodes representing the output variables created for each column that is read by the operator. The correspondingvariablefields will be set to the variable names assigned to the columns.- Type
- class Kind(value)[source]¶
Bases:
proto.enums.EnumThe kind of [PlanNode][google.spanner.v1.PlanNode]. Distinguishes between the two different kinds of nodes that can appear in a query plan.
- Values:
- KIND_UNSPECIFIED (0):
Not specified.
- RELATIONAL (1):
Denotes a Relational operator node in the expression tree. Relational operators represent iterative processing of rows during query execution. For example, a
TableScanoperation that reads rows from a table.- SCALAR (2):
Denotes a Scalar node in the expression tree. Scalar nodes represent non-iterable entities in the query plan. For example, constants or arithmetic operators appearing inside predicate expressions or references to column names.
- class ShortRepresentation(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageCondensed representation of a node and its subtree. Only present for
SCALAR[PlanNode(s)][google.spanner.v1.PlanNode].- subqueries¶
A mapping of (subquery variable name) -> (subquery node id) for cases where the
descriptionstring of this node references aSCALARsubquery contained in the expression subtree rooted at this node. The referencedSCALARsubquery may not necessarily be a direct child of this node.
- class SubqueriesEntry(mapping=None, *, ignore_unknown_fields=False, **kwargs)¶
Bases:
proto.message.Message
- class google.cloud.spanner_v1.types.QueryPlan(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageContains an ordered list of nodes appearing in the query plan.
- plan_nodes¶
The nodes in the query plan. Plan nodes are returned in pre-order starting with the plan root. Each [PlanNode][google.spanner.v1.PlanNode]’s
idcorresponds to its index inplan_nodes.- Type
MutableSequence[google.cloud.spanner_v1.types.PlanNode]
- class google.cloud.spanner_v1.types.ReadRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [Read][google.spanner.v1.Spanner.Read] and [StreamingRead][google.spanner.v1.Spanner.StreamingRead].
- transaction¶
The transaction to use. If none is provided, the default is a temporary read-only transaction with strong concurrency.
- index¶
If non-empty, the name of an index on [table][google.spanner.v1.ReadRequest.table]. This index is used instead of the table primary key when interpreting [key_set][google.spanner.v1.ReadRequest.key_set] and sorting result rows. See [key_set][google.spanner.v1.ReadRequest.key_set] for further information.
- Type
- columns¶
Required. The columns of [table][google.spanner.v1.ReadRequest.table] to be returned for each row matching this request.
- Type
MutableSequence[str]
- key_set¶
Required.
key_setidentifies the rows to be yielded.key_setnames the primary keys of the rows in [table][google.spanner.v1.ReadRequest.table] to be yielded, unless [index][google.spanner.v1.ReadRequest.index] is present. If [index][google.spanner.v1.ReadRequest.index] is present, then [key_set][google.spanner.v1.ReadRequest.key_set] instead names index keys in [index][google.spanner.v1.ReadRequest.index].If the [partition_token][google.spanner.v1.ReadRequest.partition_token] field is empty, rows are yielded in table primary key order (if [index][google.spanner.v1.ReadRequest.index] is empty) or index key order (if [index][google.spanner.v1.ReadRequest.index] is non-empty). If the [partition_token][google.spanner.v1.ReadRequest.partition_token] field is not empty, rows will be yielded in an unspecified order.
It is not an error for the
key_setto name rows that do not exist in the database. Read yields nothing for nonexistent rows.
- limit¶
If greater than zero, only the first
limitrows are yielded. Iflimitis zero, the default is no limit. A limit cannot be specified ifpartition_tokenis set.- Type
- resume_token¶
If this request is resuming a previously interrupted read,
resume_tokenshould be copied from the last [PartialResultSet][google.spanner.v1.PartialResultSet] yielded before the interruption. Doing this enables the new read to resume where the last read left off. The rest of the request parameters must exactly match the request that yielded this token.- Type
- partition_token¶
If present, results will be restricted to the specified partition previously created using PartitionRead(). There must be an exact match for the values of fields common to this message and the PartitionReadRequest message used to create this partition_token.
- Type
- request_options¶
Common options for this request.
- directed_read_options¶
Directed read options for this request.
- data_boost_enabled¶
If this is for a partitioned read and this field is set to
true, the request is executed with Spanner Data Boost independent compute resources.If the field is set to
truebut the request does not setpartition_token, the API returns anINVALID_ARGUMENTerror.- Type
- order_by¶
Optional. Order for the returned rows.
By default, Spanner will return result rows in primary key order except for PartitionRead requests. For applications that do not require rows to be returned in primary key (
ORDER_BY_PRIMARY_KEY) order, settingORDER_BY_NO_ORDERoption allows Spanner to optimize row retrieval, resulting in lower latencies in certain cases (e.g. bulk point lookups).
- lock_hint¶
Optional. Lock Hint for the request, it can only be used with read-write transactions.
- class LockHint(value)[source]¶
Bases:
proto.enums.EnumA lock hint mechanism for reads done within a transaction.
- Values:
- LOCK_HINT_UNSPECIFIED (0):
Default value.
LOCK_HINT_UNSPECIFIED is equivalent to LOCK_HINT_SHARED.
- LOCK_HINT_SHARED (1):
Acquire shared locks.
By default when you perform a read as part of a read-write transaction, Spanner acquires shared read locks, which allows other reads to still access the data until your transaction is ready to commit. When your transaction is committing and writes are being applied, the transaction attempts to upgrade to an exclusive lock for any data you are writing. For more information about locks, see Lock modes.
- LOCK_HINT_EXCLUSIVE (2):
Acquire exclusive locks.
Requesting exclusive locks is beneficial if you observe high write contention, which means you notice that multiple transactions are concurrently trying to read and write to the same data, resulting in a large number of aborts. This problem occurs when two transactions initially acquire shared locks and then both try to upgrade to exclusive locks at the same time. In this situation both transactions are waiting for the other to give up their lock, resulting in a deadlocked situation. Spanner is able to detect this occurring and force one of the transactions to abort. However, this is a slow and expensive operation and results in lower performance. In this case it makes sense to acquire exclusive locks at the start of the transaction because then when multiple transactions try to act on the same data, they automatically get serialized. Each transaction waits its turn to acquire the lock and avoids getting into deadlock situations.
Because the exclusive lock hint is just a hint, it should not be considered equivalent to a mutex. In other words, you should not use Spanner exclusive locks as a mutual exclusion mechanism for the execution of code outside of Spanner.
Note: Request exclusive locks judiciously because they block others from reading that data for the entire transaction, rather than just when the writes are being performed. Unless you observe high write contention, you should use the default of shared read locks so you don’t prematurely block other clients from reading the data that you’re writing to.
- class OrderBy(value)[source]¶
Bases:
proto.enums.EnumAn option to control the order in which rows are returned from a read.
- Values:
- ORDER_BY_UNSPECIFIED (0):
Default value.
ORDER_BY_UNSPECIFIED is equivalent to ORDER_BY_PRIMARY_KEY.
- ORDER_BY_PRIMARY_KEY (1):
Read rows are returned in primary key order.
In the event that this option is used in conjunction with the
partition_tokenfield, the API will return anINVALID_ARGUMENTerror.- ORDER_BY_NO_ORDER (2):
Read rows are returned in any order.
- class google.cloud.spanner_v1.types.RequestOptions(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageCommon request options for various APIs.
- priority¶
Priority for the request.
- request_tag¶
A per-request tag which can be applied to queries or reads, used for statistics collection. Both request_tag and transaction_tag can be specified for a read or query that belongs to a transaction. This field is ignored for requests where it’s not applicable (e.g. CommitRequest). Legal characters for
request_tagvalues are all printable characters (ASCII 32 - 126) and the length of a request_tag is limited to 50 characters. Values that exceed this limit are truncated. Any leading underscore (_) characters will be removed from the string.- Type
- transaction_tag¶
A tag used for statistics collection about this transaction. Both request_tag and transaction_tag can be specified for a read or query that belongs to a transaction. The value of transaction_tag should be the same for all requests belonging to the same transaction. If this request doesn’t belong to any transaction, transaction_tag will be ignored. Legal characters for
transaction_tagvalues are all printable characters (ASCII 32 - 126) and the length of a transaction_tag is limited to 50 characters. Values that exceed this limit are truncated. Any leading underscore (_) characters will be removed from the string.- Type
- class Priority(value)[source]¶
Bases:
proto.enums.EnumThe relative priority for requests. Note that priority is not applicable for [BeginTransaction][google.spanner.v1.Spanner.BeginTransaction].
The priority acts as a hint to the Cloud Spanner scheduler and does not guarantee priority or order of execution. For example:
Some parts of a write operation always execute at
PRIORITY_HIGH, regardless of the specified priority. This may cause you to see an increase in high priority workload even when executing a low priority request. This can also potentially cause a priority inversion where a lower priority request will be fulfilled ahead of a higher priority request.If a transaction contains multiple operations with different priorities, Cloud Spanner does not guarantee to process the higher priority operations first. There may be other constraints to satisfy, such as order of operations.
- Values:
- PRIORITY_UNSPECIFIED (0):
PRIORITY_UNSPECIFIEDis equivalent toPRIORITY_HIGH.- PRIORITY_LOW (1):
This specifies that the request is low priority.
- PRIORITY_MEDIUM (2):
This specifies that the request is medium priority.
- PRIORITY_HIGH (3):
This specifies that the request is high priority.
- class google.cloud.spanner_v1.types.ResultSet(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageResults from [Read][google.spanner.v1.Spanner.Read] or [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql].
- metadata¶
Metadata about the result set, such as row type information.
- rows¶
Each element in
rowsis a row whose format is defined by [metadata.row_type][google.spanner.v1.ResultSetMetadata.row_type]. The ith element in each row matches the ith field in [metadata.row_type][google.spanner.v1.ResultSetMetadata.row_type]. Elements are encoded based on type as described [here][google.spanner.v1.TypeCode].- Type
MutableSequence[google.protobuf.struct_pb2.ListValue]
- stats¶
Query plan and execution statistics for the SQL statement that produced this result set. These can be requested by setting [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode]. DML statements always produce stats containing the number of rows modified, unless executed using the [ExecuteSqlRequest.QueryMode.PLAN][google.spanner.v1.ExecuteSqlRequest.QueryMode.PLAN] [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode]. Other fields may or may not be populated, based on the [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode].
- precommit_token¶
Optional. A precommit token will be included if the read-write transaction is on a multiplexed session. The precommit token with the highest sequence number from this transaction attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit] request for this transaction. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- class google.cloud.spanner_v1.types.ResultSetMetadata(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageMetadata about a [ResultSet][google.spanner.v1.ResultSet] or [PartialResultSet][google.spanner.v1.PartialResultSet].
- row_type¶
Indicates the field names and types for the rows in the result set. For example, a SQL query like
"SELECT UserId, UserName FROM Users"could return arow_typevalue like:"fields": [ { "name": "UserId", "type": { "code": "INT64" } }, { "name": "UserName", "type": { "code": "STRING" } }, ]
- transaction¶
If the read or SQL query began a transaction as a side-effect, the information about the new transaction is yielded here.
- undeclared_parameters¶
A SQL query can be parameterized. In PLAN mode, these parameters can be undeclared. This indicates the field names and types for those undeclared parameters in the SQL query. For example, a SQL query like
"SELECT * FROM Users where UserId = @userId and UserName = @userName "could return aundeclared_parametersvalue like:"fields": [ { "name": "UserId", "type": { "code": "INT64" } }, { "name": "UserName", "type": { "code": "STRING" } }, ]
- class google.cloud.spanner_v1.types.ResultSetStats(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageAdditional statistics about a [ResultSet][google.spanner.v1.ResultSet] or [PartialResultSet][google.spanner.v1.PartialResultSet].
This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- query_plan¶
[QueryPlan][google.spanner.v1.QueryPlan] for the query associated with this result.
- query_stats¶
Aggregated statistics from the execution of the query. Only present when the query is profiled. For example, a query could return the statistics as follows:
{ "rows_returned": "3", "elapsed_time": "1.22 secs", "cpu_time": "1.19 secs" }
- class google.cloud.spanner_v1.types.RollbackRequest(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThe request for [Rollback][google.spanner.v1.Spanner.Rollback].
- class google.cloud.spanner_v1.types.Session(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageA session in the Cloud Spanner API.
- labels¶
The labels for the session.
Label keys must be between 1 and 63 characters long and must conform to the following regular expression:
[a-z]([-a-z0-9]*[a-z0-9])?.Label values must be between 0 and 63 characters long and must conform to the regular expression
([a-z]([-a-z0-9]*[a-z0-9])?)?.No more than 64 labels can be associated with a given session.
See https://goo.gl/xmQnxf for more information on and examples of labels.
- create_time¶
Output only. The timestamp when the session is created.
- approximate_last_use_time¶
Output only. The approximate timestamp when the session is last used. It is typically earlier than the actual last use time.
- multiplexed¶
Optional. If true, specifies a multiplexed session. A multiplexed session may be used for multiple, concurrent read-only operations but can not be used for read-write transactions, partitioned reads, or partitioned queries. Multiplexed sessions can be created via [CreateSession][google.spanner.v1.Spanner.CreateSession] but not via [BatchCreateSessions][google.spanner.v1.Spanner.BatchCreateSessions]. Multiplexed sessions may not be deleted nor listed.
- Type
- class LabelsEntry(mapping=None, *, ignore_unknown_fields=False, **kwargs)¶
Bases:
proto.message.Message
- class google.cloud.spanner_v1.types.StructType(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageStructTypedefines the fields of a [STRUCT][google.spanner.v1.TypeCode.STRUCT] type.- fields¶
The list of fields that make up this struct. Order is significant, because values of this struct type are represented as lists, where the order of field values matches the order of fields in the [StructType][google.spanner.v1.StructType]. In turn, the order of fields matches the order of columns in a read request, or the order of fields in the
SELECTclause of a query.- Type
MutableSequence[google.cloud.spanner_v1.types.StructType.Field]
- class Field(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageMessage representing a single field of a struct.
- name¶
The name of the field. For reads, this is the column name. For SQL queries, it is the column alias (e.g.,
"Word"in the query"SELECT 'hello' AS Word"), or the column name (e.g.,"ColName"in the query"SELECT ColName FROM Table"). Some columns might have an empty name (e.g.,"SELECT UPPER(ColName)"). Note that a query result can contain multiple fields with the same name.- Type
- type_¶
The type of the field.
- class google.cloud.spanner_v1.types.Transaction(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageA transaction.
- id¶
idmay be used to identify the transaction in subsequent [Read][google.spanner.v1.Spanner.Read], [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql], [Commit][google.spanner.v1.Spanner.Commit], or [Rollback][google.spanner.v1.Spanner.Rollback] calls.Single-use read-only transactions do not have IDs, because single-use transactions do not support multiple requests.
- Type
- read_timestamp¶
For snapshot read-only transactions, the read timestamp chosen for the transaction. Not returned by default: see [TransactionOptions.ReadOnly.return_read_timestamp][google.spanner.v1.TransactionOptions.ReadOnly.return_read_timestamp].
A timestamp in RFC3339 UTC “Zulu” format, accurate to nanoseconds. Example:
"2014-10-02T15:01:23.045123456Z".
- precommit_token¶
A precommit token will be included in the response of a BeginTransaction request if the read-write transaction is on a multiplexed session and a mutation_key was specified in the [BeginTransaction][google.spanner.v1.BeginTransactionRequest]. The precommit token with the highest sequence number from this transaction attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit] request for this transaction. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- class google.cloud.spanner_v1.types.TransactionOptions(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageTransactions:
Each session can have at most one active transaction at a time (note that standalone reads and queries use a transaction internally and do count towards the one transaction limit). After the active transaction is completed, the session can immediately be re-used for the next transaction. It is not necessary to create a new session for each transaction.
Transaction modes:
Cloud Spanner supports three transaction modes:
Locking read-write. This type of transaction is the only way to write data into Cloud Spanner. These transactions rely on pessimistic locking and, if necessary, two-phase commit. Locking read-write transactions may abort, requiring the application to retry.
Snapshot read-only. Snapshot read-only transactions provide guaranteed consistency across several reads, but do not allow writes. Snapshot read-only transactions can be configured to read at timestamps in the past, or configured to perform a strong read (where Spanner will select a timestamp such that the read is guaranteed to see the effects of all transactions that have committed before the start of the read). Snapshot read-only transactions do not need to be committed.
Queries on change streams must be performed with the snapshot read-only transaction mode, specifying a strong read. Please see [TransactionOptions.ReadOnly.strong][google.spanner.v1.TransactionOptions.ReadOnly.strong] for more details.
Partitioned DML. This type of transaction is used to execute a single Partitioned DML statement. Partitioned DML partitions the key space and runs the DML statement over each partition in parallel using separate, internal transactions that commit independently. Partitioned DML transactions do not need to be committed.
For transactions that only read, snapshot read-only transactions provide simpler semantics and are almost always faster. In particular, read-only transactions do not take locks, so they do not conflict with read-write transactions. As a consequence of not taking locks, they also do not abort, so retry loops are not needed.
Transactions may only read-write data in a single database. They may, however, read-write data in different tables within that database.
Locking read-write transactions:
Locking transactions may be used to atomically read-modify-write data anywhere in a database. This type of transaction is externally consistent.
Clients should attempt to minimize the amount of time a transaction is active. Faster transactions commit with higher probability and cause less contention. Cloud Spanner attempts to keep read locks active as long as the transaction continues to do reads, and the transaction has not been terminated by [Commit][google.spanner.v1.Spanner.Commit] or [Rollback][google.spanner.v1.Spanner.Rollback]. Long periods of inactivity at the client may cause Cloud Spanner to release a transaction’s locks and abort it.
Conceptually, a read-write transaction consists of zero or more reads or SQL statements followed by [Commit][google.spanner.v1.Spanner.Commit]. At any time before [Commit][google.spanner.v1.Spanner.Commit], the client can send a [Rollback][google.spanner.v1.Spanner.Rollback] request to abort the transaction.
Semantics:
Cloud Spanner can commit the transaction if all read locks it acquired are still valid at commit time, and it is able to acquire write locks for all writes. Cloud Spanner can abort the transaction for any reason. If a commit attempt returns
ABORTED, Cloud Spanner guarantees that the transaction has not modified any user data in Cloud Spanner.Unless the transaction commits, Cloud Spanner makes no guarantees about how long the transaction’s locks were held for. It is an error to use Cloud Spanner locks for any sort of mutual exclusion other than between Cloud Spanner transactions themselves.
Retrying aborted transactions:
When a transaction aborts, the application can choose to retry the whole transaction again. To maximize the chances of successfully committing the retry, the client should execute the retry in the same session as the original attempt. The original session’s lock priority increases with each consecutive abort, meaning that each attempt has a slightly better chance of success than the previous.
Under some circumstances (for example, many transactions attempting to modify the same row(s)), a transaction can abort many times in a short period before successfully committing. Thus, it is not a good idea to cap the number of retries a transaction can attempt; instead, it is better to limit the total amount of time spent retrying.
Idle transactions:
A transaction is considered idle if it has no outstanding reads or SQL queries and has not started a read or SQL query within the last 10 seconds. Idle transactions can be aborted by Cloud Spanner so that they don’t hold on to locks indefinitely. If an idle transaction is aborted, the commit will fail with error
ABORTED.If this behavior is undesirable, periodically executing a simple SQL query in the transaction (for example,
SELECT 1) prevents the transaction from becoming idle.Snapshot read-only transactions:
Snapshot read-only transactions provides a simpler method than locking read-write transactions for doing several consistent reads. However, this type of transaction does not support writes.
Snapshot transactions do not take locks. Instead, they work by choosing a Cloud Spanner timestamp, then executing all reads at that timestamp. Since they do not acquire locks, they do not block concurrent read-write transactions.
Unlike locking read-write transactions, snapshot read-only transactions never abort. They can fail if the chosen read timestamp is garbage collected; however, the default garbage collection policy is generous enough that most applications do not need to worry about this in practice.
Snapshot read-only transactions do not need to call [Commit][google.spanner.v1.Spanner.Commit] or [Rollback][google.spanner.v1.Spanner.Rollback] (and in fact are not permitted to do so).
To execute a snapshot transaction, the client specifies a timestamp bound, which tells Cloud Spanner how to choose a read timestamp.
The types of timestamp bound are:
Strong (the default).
Bounded staleness.
Exact staleness.
If the Cloud Spanner database to be read is geographically distributed, stale read-only transactions can execute more quickly than strong or read-write transactions, because they are able to execute far from the leader replica.
Each type of timestamp bound is discussed in detail below.
Strong: Strong reads are guaranteed to see the effects of all transactions that have committed before the start of the read. Furthermore, all rows yielded by a single read are consistent with each other – if any part of the read observes a transaction, all parts of the read see the transaction.
Strong reads are not repeatable: two consecutive strong read-only transactions might return inconsistent results if there are concurrent writes. If consistency across reads is required, the reads should be executed within a transaction or at an exact read timestamp.
Queries on change streams (see below for more details) must also specify the strong read timestamp bound.
See [TransactionOptions.ReadOnly.strong][google.spanner.v1.TransactionOptions.ReadOnly.strong].
Exact staleness:
These timestamp bounds execute reads at a user-specified timestamp. Reads at a timestamp are guaranteed to see a consistent prefix of the global transaction history: they observe modifications done by all transactions with a commit timestamp less than or equal to the read timestamp, and observe none of the modifications done by transactions with a larger commit timestamp. They will block until all conflicting transactions that may be assigned commit timestamps <= the read timestamp have finished.
The timestamp can either be expressed as an absolute Cloud Spanner commit timestamp or a staleness relative to the current time.
These modes do not require a “negotiation phase” to pick a timestamp. As a result, they execute slightly faster than the equivalent boundedly stale concurrency modes. On the other hand, boundedly stale reads usually return fresher results.
See [TransactionOptions.ReadOnly.read_timestamp][google.spanner.v1.TransactionOptions.ReadOnly.read_timestamp] and [TransactionOptions.ReadOnly.exact_staleness][google.spanner.v1.TransactionOptions.ReadOnly.exact_staleness].
Bounded staleness:
Bounded staleness modes allow Cloud Spanner to pick the read timestamp, subject to a user-provided staleness bound. Cloud Spanner chooses the newest timestamp within the staleness bound that allows execution of the reads at the closest available replica without blocking.
All rows yielded are consistent with each other – if any part of the read observes a transaction, all parts of the read see the transaction. Boundedly stale reads are not repeatable: two stale reads, even if they use the same staleness bound, can execute at different timestamps and thus return inconsistent results.
Boundedly stale reads execute in two phases: the first phase negotiates a timestamp among all replicas needed to serve the read. In the second phase, reads are executed at the negotiated timestamp.
As a result of the two phase execution, bounded staleness reads are usually a little slower than comparable exact staleness reads. However, they are typically able to return fresher results, and are more likely to execute at the closest replica.
Because the timestamp negotiation requires up-front knowledge of which rows will be read, it can only be used with single-use read-only transactions.
See [TransactionOptions.ReadOnly.max_staleness][google.spanner.v1.TransactionOptions.ReadOnly.max_staleness] and [TransactionOptions.ReadOnly.min_read_timestamp][google.spanner.v1.TransactionOptions.ReadOnly.min_read_timestamp].
Old read timestamps and garbage collection:
Cloud Spanner continuously garbage collects deleted and overwritten data in the background to reclaim storage space. This process is known as “version GC”. By default, version GC reclaims versions after they are one hour old. Because of this, Cloud Spanner cannot perform reads at read timestamps more than one hour in the past. This restriction also applies to in-progress reads and/or SQL queries whose timestamp become too old while executing. Reads and SQL queries with too-old read timestamps fail with the error
FAILED_PRECONDITION.You can configure and extend the
VERSION_RETENTION_PERIODof a database up to a period as long as one week, which allows Cloud Spanner to perform reads up to one week in the past.Querying change Streams:
A Change Stream is a schema object that can be configured to watch data changes on the entire database, a set of tables, or a set of columns in a database.
When a change stream is created, Spanner automatically defines a corresponding SQL Table-Valued Function (TVF) that can be used to query the change records in the associated change stream using the ExecuteStreamingSql API. The name of the TVF for a change stream is generated from the name of the change stream: READ_<change_stream_name>.
All queries on change stream TVFs must be executed using the ExecuteStreamingSql API with a single-use read-only transaction with a strong read-only timestamp_bound. The change stream TVF allows users to specify the start_timestamp and end_timestamp for the time range of interest. All change records within the retention period is accessible using the strong read-only timestamp_bound. All other TransactionOptions are invalid for change stream queries.
In addition, if TransactionOptions.read_only.return_read_timestamp is set to true, a special value of 2^63 - 2 will be returned in the [Transaction][google.spanner.v1.Transaction] message that describes the transaction, instead of a valid read timestamp. This special value should be discarded and not used for any subsequent queries.
Please see https://cloud.google.com/spanner/docs/change-streams for more details on how to query the change stream TVFs.
Partitioned DML transactions:
Partitioned DML transactions are used to execute DML statements with a different execution strategy that provides different, and often better, scalability properties for large, table-wide operations than DML in a ReadWrite transaction. Smaller scoped statements, such as an OLTP workload, should prefer using ReadWrite transactions.
Partitioned DML partitions the keyspace and runs the DML statement on each partition in separate, internal transactions. These transactions commit automatically when complete, and run independently from one another.
To reduce lock contention, this execution strategy only acquires read locks on rows that match the WHERE clause of the statement. Additionally, the smaller per-partition transactions hold locks for less time.
That said, Partitioned DML is not a drop-in replacement for standard DML used in ReadWrite transactions.
The DML statement must be fully-partitionable. Specifically, the statement must be expressible as the union of many statements which each access only a single row of the table.
The statement is not applied atomically to all rows of the table. Rather, the statement is applied atomically to partitions of the table, in independent transactions. Secondary index rows are updated atomically with the base table rows.
Partitioned DML does not guarantee exactly-once execution semantics against a partition. The statement will be applied at least once to each partition. It is strongly recommended that the DML statement should be idempotent to avoid unexpected results. For instance, it is potentially dangerous to run a statement such as
UPDATE table SET column = column + 1as it could be run multiple times against some rows.The partitions are committed automatically - there is no support for Commit or Rollback. If the call returns an error, or if the client issuing the ExecuteSql call dies, it is possible that some rows had the statement executed on them successfully. It is also possible that statement was never executed against other rows.
Partitioned DML transactions may only contain the execution of a single DML statement via ExecuteSql or ExecuteStreamingSql.
If any error is encountered during the execution of the partitioned DML operation (for instance, a UNIQUE INDEX violation, division by zero, or a value that cannot be stored due to schema constraints), then the operation is stopped at that point and an error is returned. It is possible that at this point, some partitions have been committed (or even committed multiple times), and other partitions have not been run at all.
Given the above, Partitioned DML is good fit for large, database-wide, operations that are idempotent, such as deleting old rows from a very large table.
This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- read_write¶
Transaction may write.
Authorization to begin a read-write transaction requires
spanner.databases.beginOrRollbackReadWriteTransactionpermission on thesessionresource.This field is a member of oneof
mode.
- partitioned_dml¶
Partitioned DML transaction.
Authorization to begin a Partitioned DML transaction requires
spanner.databases.beginPartitionedDmlTransactionpermission on thesessionresource.This field is a member of oneof
mode.
- read_only¶
Transaction will not write.
Authorization to begin a read-only transaction requires
spanner.databases.beginReadOnlyTransactionpermission on thesessionresource.This field is a member of oneof
mode.
- exclude_txn_from_change_streams¶
When
exclude_txn_from_change_streamsis set totrue:Mutations from this transaction will not be recorded in change streams with DDL option
allow_txn_exclusion=truethat are tracking columns modified by these transactions.Mutations from this transaction will be recorded in change streams with DDL option
allow_txn_exclusion=false or not setthat are tracking columns modified by these transactions.
When
exclude_txn_from_change_streamsis set tofalseor not set, mutations from this transaction will be recorded in all change streams that are tracking columns modified by these transactions.exclude_txn_from_change_streamsmay only be specified for read-write or partitioned-dml transactions, otherwise the API will return anINVALID_ARGUMENTerror.- Type
- class PartitionedDml(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageMessage type to initiate a Partitioned DML transaction.
- class ReadOnly(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageMessage type to initiate a read-only transaction.
This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- strong¶
Read at a timestamp where all previously committed transactions are visible.
This field is a member of oneof
timestamp_bound.- Type
- min_read_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".This field is a member of oneof
timestamp_bound.
- max_staleness¶
Read data at a timestamp >=
NOW - max_stalenessseconds. 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.
This field is a member of oneof
timestamp_bound.
- read_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".This field is a member of oneof
timestamp_bound.
- exact_staleness¶
Executes all reads at a timestamp that is
exact_stalenessold. 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.This field is a member of oneof
timestamp_bound.
- class ReadWrite(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageMessage type to initiate a read-write transaction. Currently this transaction type has no options.
- read_lock_mode¶
Read lock mode for the transaction.
- multiplexed_session_previous_transaction_id¶
Optional. Clients should pass the transaction ID of the previous transaction attempt that was aborted if this transaction is being executed on a multiplexed session. This feature is not yet supported and will result in an UNIMPLEMENTED error.
- Type
- class ReadLockMode(value)[source]¶
Bases:
proto.enums.EnumReadLockModeis used to set the read lock mode for read-write transactions.- Values:
- READ_LOCK_MODE_UNSPECIFIED (0):
Default value.
If the value is not specified, the pessimistic read lock is used.
- PESSIMISTIC (1):
Pessimistic lock mode.
Read locks are acquired immediately on read.
- OPTIMISTIC (2):
Optimistic lock mode.
Locks for reads within the transaction are not acquired on read. Instead the locks are acquired on a commit to validate that read/queried data has not changed since the transaction started.
- class google.cloud.spanner_v1.types.TransactionSelector(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageThis message is used to select the transaction in which a [Read][google.spanner.v1.Spanner.Read] or [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql] call runs.
See [TransactionOptions][google.spanner.v1.TransactionOptions] for more information about transactions.
This message has oneof fields (mutually exclusive fields). For each oneof, at most one member field can be set at the same time. Setting any member of the oneof automatically clears all other members.
- single_use¶
Execute the read or SQL query in a temporary transaction. This is the most efficient way to execute a transaction that consists of a single SQL query.
This field is a member of oneof
selector.
- id¶
Execute the read or SQL query in a previously-started transaction.
This field is a member of oneof
selector.- Type
- begin¶
Begin a new transaction and execute this read or SQL query in it. The transaction ID of the new transaction is returned in [ResultSetMetadata.transaction][google.spanner.v1.ResultSetMetadata.transaction], which is a [Transaction][google.spanner.v1.Transaction].
This field is a member of oneof
selector.
- class google.cloud.spanner_v1.types.Type(mapping=None, *, ignore_unknown_fields=False, **kwargs)[source]¶
Bases:
proto.message.MessageTypeindicates the type of a Cloud Spanner value, as might be stored in a table cell or returned from an SQL query.- code¶
Required. The [TypeCode][google.spanner.v1.TypeCode] for this type.
- array_element_type¶
If [code][google.spanner.v1.Type.code] == [ARRAY][google.spanner.v1.TypeCode.ARRAY], then
array_element_typeis the type of the array elements.
- struct_type¶
If [code][google.spanner.v1.Type.code] == [STRUCT][google.spanner.v1.TypeCode.STRUCT], then
struct_typeprovides type information for the struct’s fields.
- type_annotation¶
The [TypeAnnotationCode][google.spanner.v1.TypeAnnotationCode] that disambiguates SQL type that Spanner will use to represent values of this type during query processing. This is necessary for some type codes because a single [TypeCode][google.spanner.v1.TypeCode] can be mapped to different SQL types depending on the SQL dialect. [type_annotation][google.spanner.v1.Type.type_annotation] typically is not needed to process the content of a value (it doesn’t affect serialization) and clients can ignore it on the read path.
- class google.cloud.spanner_v1.types.TypeAnnotationCode(value)[source]¶
Bases:
proto.enums.EnumTypeAnnotationCodeis used as a part of [Type][google.spanner.v1.Type] to disambiguate SQL types that should be used for a given Cloud Spanner value. Disambiguation is needed because the same Cloud Spanner type can be mapped to different SQL types depending on SQL dialect. TypeAnnotationCode doesn’t affect the way value is serialized.- Values:
- TYPE_ANNOTATION_CODE_UNSPECIFIED (0):
Not specified.
- PG_NUMERIC (2):
PostgreSQL compatible NUMERIC type. This annotation needs to be applied to [Type][google.spanner.v1.Type] instances having [NUMERIC][google.spanner.v1.TypeCode.NUMERIC] type code to specify that values of this type should be treated as PostgreSQL NUMERIC values. Currently this annotation is always needed for [NUMERIC][google.spanner.v1.TypeCode.NUMERIC] when a client interacts with PostgreSQL-enabled Spanner databases.
- PG_JSONB (3):
PostgreSQL compatible JSONB type. This annotation needs to be applied to [Type][google.spanner.v1.Type] instances having [JSON][google.spanner.v1.TypeCode.JSON] type code to specify that values of this type should be treated as PostgreSQL JSONB values. Currently this annotation is always needed for [JSON][google.spanner.v1.TypeCode.JSON] when a client interacts with PostgreSQL-enabled Spanner databases.
- PG_OID (4):
PostgreSQL compatible OID type. This annotation can be used by a client interacting with PostgreSQL-enabled Spanner database to specify that a value should be treated using the semantics of the OID type.
- class google.cloud.spanner_v1.types.TypeCode(value)[source]¶
Bases:
proto.enums.EnumTypeCodeis used as part of [Type][google.spanner.v1.Type] to indicate the type of a Cloud Spanner value.Each legal value of a type can be encoded to or decoded from a JSON value, using the encodings described below. All Cloud Spanner values can be
null, regardless of type;nulls are always encoded as a JSONnull.- Values:
- TYPE_CODE_UNSPECIFIED (0):
Not specified.
- BOOL (1):
Encoded as JSON
trueorfalse.- INT64 (2):
Encoded as
string, in decimal format.- FLOAT64 (3):
Encoded as
number, or the strings"NaN","Infinity", or"-Infinity".- FLOAT32 (15):
Encoded as
number, or the strings"NaN","Infinity", or"-Infinity".- TIMESTAMP (4):
Encoded as
stringin RFC 3339 timestamp format. The time zone must be present, and must be"Z".If the schema has the column option
allow_commit_timestamp=true, the placeholder string"spanner.commit_timestamp()"can be used to instruct the system to insert the commit timestamp associated with the transaction commit.- DATE (5):
Encoded as
stringin RFC 3339 date format.- STRING (6):
Encoded as
string.- BYTES (7):
Encoded as a base64-encoded
string, as described in RFC 4648, section 4.- ARRAY (8):
Encoded as
list, where the list elements are represented according to [array_element_type][google.spanner.v1.Type.array_element_type].- STRUCT (9):
Encoded as
list, where list elementiis represented according to [struct_type.fields[i]][google.spanner.v1.StructType.fields].- NUMERIC (10):
Encoded as
string, in decimal format or scientific notation format. Decimal format:[+-]Digits[.[Digits]]or[+-][Digits].DigitsScientific notation:
[+-]Digits[.[Digits]][ExponentIndicator[+-]Digits]or[+-][Digits].Digits[ExponentIndicator[+-]Digits](ExponentIndicator is"e"or"E")- JSON (11):
Encoded as a JSON-formatted
stringas described in RFC 7159. The following rules are applied when parsing JSON input:Whitespace characters are not preserved.
If a JSON object has duplicate keys, only the first key is preserved.
Members of a JSON object are not guaranteed to have their order preserved.
JSON array elements will have their order preserved.
- PROTO (13):
Encoded as a base64-encoded
string, as described in RFC 4648, section 4.- ENUM (14):
Encoded as
string, in decimal format.- INTERVAL (16):
Encoded as
string, inISO8601duration format -P[n]Y[n]M[n]DT[n]H[n]M[n[.fraction]]Swherenis an integer. For example,P1Y2M3DT4H5M6.5Srepresents time duration of 1 year, 2 months, 3 days, 4 hours, 5 minutes, and 6.5 seconds.
