Interface Connection (6.58.0)

Internal connection API for Google Cloud Spanner. This interface may introduce breaking changes without prior notice.

A connection to a Cloud Spanner database. Connections are not designed to be thread-safe. The only exception is the Connection#cancel() method that may be called by any other thread to stop the execution of the current statement on the connection.

All -Async methods on Connection are guaranteed to be executed in the order that they are issued on the Connection. Mixing synchronous and asynchronous method calls is also supported, and these are also guaranteed to be executed in the order that they are issued.

Connections accept a number of additional SQL statements for setting or changing the state of a Connection. These statements can only be executed using the Connection#execute(Statement) method:

• SHOW AUTOCOMMIT: Returns the current value of AUTOCOMMIT of this connection as a ResultSet
• SET AUTOCOMMIT=TRUE|FALSE: Sets the value of AUTOCOMMIT for this connection
• SHOW READONLY: Returns the current value of READONLY of this connection as a ResultSet
• SET READONLY=TRUE|FALSE: Sets the value of READONLY for this connection
• SHOW RETRY_ABORTS_INTERNALLY: Returns the current value of RETRY_ABORTS_INTERNALLY of this connection as a ResultSet
• SET RETRY_ABORTS_INTERNALLY=TRUE|FALSE: Sets the value of RETRY_ABORTS_INTERNALLY for this connection
• SHOW AUTOCOMMIT_DML_MODE: Returns the current value of AUTOCOMMIT_DML_MODE of this connection as a ResultSet
• SET AUTOCOMMIT_DML_MODE='TRANSACTIONAL' | 'PARTITIONED_NON_ATOMIC': Sets the value of AUTOCOMMIT_DML_MODE for this connection
• SHOW STATEMENT_TIMEOUT: Returns the current value of STATEMENT_TIMEOUT of this connection as a ResultSet
• SET STATEMENT_TIMEOUT='<int64>s|ms|us|ns' | NULL: Sets the value of STATEMENT_TIMEOUT for this connection. The supported TimeUnits are:
  • s - Seconds
  • ms - Milliseconds
  • us - Microseconds
  • ns - Nanoseconds

Note that Cloud Spanner could abort read/write transactions in the background, and that any database call during a read/write transaction could fail with an AbortedException. This also includes calls to ResultSet#next().

If Connection#isRetryAbortsInternally() is true, then the connection will silently handle any AbortedExceptions by internally re-acquiring all transactional locks and verifying (via the use of cryptographic checksums) that no underlying data has changed. If a change to the underlying data is detected, then an AbortedDueToConcurrentModificationException error will be thrown. If your application already uses retry loops to handle these Aborted errors, then it will be most efficient to set Connection#isRetryAbortsInternally() to false.

Use ConnectionOptions to create a Connection.

Clears all buffered statements in the current batch and ends the batch.

This method may only be called when a (possibly empty) batch is active.

Add a TransactionRetryListener to this Connection for testing and logging purposes. The method TransactionRetryListener#retryStarting(Timestamp, long, int) will be called before an automatic retry is started for a read/write transaction on this connection. The method TransactionRetryListener#retryFinished(Timestamp, long, int, TransactionRetryListener.RetryResult) will be called after the retry has finished.

Analyzes a query or a DML statement and returns query plan and/or query execution statistics information.

The query plan and query statistics information is contained in com.google.spanner.v1.ResultSetStats that can be accessed by calling ResultSet#getStats() on the returned ResultSet.

 
 
 ResultSet resultSet =
     connection.analyzeQuery(
         Statement.of("SELECT SingerId, AlbumId, MarketingBudget FROM Albums"),
         ReadContext.QueryAnalyzeMode.PROFILE);
 while (resultSet.next()) {
   // Discard the results. We're only processing because getStats() below requires it.
 }
 ResultSetStats stats = resultSet.getStats();
 
 
 

Deprecated. Use #analyzeUpdateStatement(Statement, QueryAnalyzeMode, UpdateOption...) instead

Analyzes a DML statement and returns query plan and/or execution statistics information.

com.google.cloud.spanner.ReadContext.QueryAnalyzeMode#PLAN only returns the plan for the statement. com.google.cloud.spanner.ReadContext.QueryAnalyzeMode#PROFILE executes the DML statement, returns the modified row count and execution statistics, and the effects of the DML statement will be visible to subsequent operations in the transaction.

Analyzes a DML statement and returns execution plan, undeclared parameters and optionally execution statistics information.

com.google.cloud.spanner.ReadContext.QueryAnalyzeMode#PLAN only returns the plan and undeclared parameters for the statement. com.google.cloud.spanner.ReadContext.QueryAnalyzeMode#PROFILE also executes the DML statement, returns the modified row count and execution statistics, and the effects of the DML statement will be visible to subsequent operations in the transaction.

Begins a new transaction for this connection.

• Calling this method on a connection that has no transaction and that is not in autocommit mode, will register a new transaction that has not yet started on this connection
• Calling this method on a connection that has no transaction and that is in autocommit mode, will register a new transaction that has not yet started on this connection, and temporarily turn off autocommit mode until the next commit/rollback
• Calling this method on a connection that already has a transaction that has not yet started, will cause a SpannerException
• Calling this method on a connection that already has a transaction that has started, will cause a SpannerException (no nested transactions)

Begins a new transaction for this connection. This method is guaranteed to be non-blocking. The returned ApiFuture will be done when the transaction has been initialized.

• Calling this method on a connection that has no transaction and that is not in autocommit mode, will register a new transaction that has not yet started on this connection
• Calling this method on a connection that has no transaction and that is in autocommit mode, will register a new transaction that has not yet started on this connection, and temporarily turn off autocommit mode until the next commit/rollback
• Calling this method on a connection that already has a transaction that has not yet started, will cause a SpannerException
• Calling this method on a connection that already has a transaction that has started, will cause a SpannerException (no nested transactions)

Buffers the given mutation locally on the current transaction of this Connection. The mutation will be written to the database at the next call to Connection#commit(). The value will not be readable on this Connection before the transaction is committed.

Calling this method is only allowed when not in autocommit mode. See Connection#write(Mutation) for writing mutations in autocommit mode.

Buffers the given mutations locally on the current transaction of this Connection. The mutations will be written to the database at the next call to Connection#commit(). The values will not be readable on this Connection before the transaction is committed.

Calling this method is only allowed when not in autocommit mode. See Connection#write(Iterable) for writing mutations in autocommit mode.

Cancels the currently running statement on this Connection (if any). If canceling the statement execution succeeds, the statement will be terminated and a SpannerException with code ErrorCode#CANCELLED will be thrown. The result of the statement will be the same as when a statement times out (see Connection#setStatementTimeout(long, TimeUnit) for more information).

Canceling a DDL statement in autocommit mode or a RUN BATCH statement of a DDL batch will cause the connection to try to cancel the execution of the DDL statement(s). This is not guaranteed to cancel the execution of the statement(s) on Cloud Spanner. See https://cloud.google.com/spanner/docs/reference/rpc/google.longrunning#google.longrunning.Operations.CancelOperation for more information.

Canceling a DML statement that is running in AutocommitDmlMode#PARTITIONED_NON_ATOMIC mode will not cancel a statement on Cloud Spanner that is already being executed, and its effects will still be applied to the database.

Clears the statement timeout value for this connection. This is a no-op if there is currently no statement timeout set on this connection.

Closes this connection. This is a no-op if the Connection has already been closed.

Closes this connection without blocking. This is a no-op if the Connection has already been closed. The Connection is no longer usable directly after calling this method. The returned ApiFuture is done when the running statement(s) (if any) on the connection have finished.

Commits the current transaction of this connection. All mutations that have been buffered during the current transaction will be written to the database.

If the connection is in autocommit mode, and there is a temporary transaction active on this connection, calling this method will cause the connection to go back to autocommit mode after calling this method.

This method will throw a SpannerException with code ErrorCode#DEADLINE_EXCEEDED if a statement timeout has been set on this connection, and the commit operation takes longer than this timeout.

• Calling this method on a connection in autocommit mode and with no temporary transaction, will cause an exception
• Calling this method while a DDL batch is active will cause an exception
• Calling this method on a connection with a transaction that has not yet started, will end that transaction and any properties that might have been set on that transaction, and return the connection to its previous state. This means that if a transaction is created and set to read-only, and then committed before any statements have been executed, the read-only transaction is ended and any subsequent statements will be executed in a new transaction. If the connection is in read-write mode, the default for new transactions will be TransactionMode#READ_WRITE_TRANSACTION. Committing an empty transaction also does not generate a read timestamp or a commit timestamp, and calling one of the methods Connection#getReadTimestamp() or Connection#getCommitTimestamp() will cause an exception.
• Calling this method on a connection with a TransactionMode#READ_ONLY_TRANSACTION transaction will end that transaction. If the connection is in read-write mode, any subsequent transaction will by default be a TransactionMode#READ_WRITE_TRANSACTION transaction, unless any following transaction is explicitly set to TransactionMode#READ_ONLY_TRANSACTION
• Calling this method on a connection with a TransactionMode#READ_WRITE_TRANSACTION transaction will send all buffered mutations to the database, commit any DML statements that have been executed during this transaction and end the transaction.

Commits the current transaction of this connection. All mutations that have been buffered during the current transaction will be written to the database.

This method is guaranteed to be non-blocking. The returned ApiFuture will be done when the transaction has committed or the commit has failed.

Calling this method will always end the current transaction and start a new transaction when the next statement is executed, regardless whether this commit call succeeded or failed. If the next statement(s) rely on the results of the transaction that is being committed, it is recommended to check the status of this commit by inspecting the value of the returned ApiFuture before executing the next statement, to ensure that the commit actually succeeded.

If the connection is in autocommit mode, and there is a temporary transaction active on this connection, calling this method will cause the connection to go back to autocommit mode after calling this method.

This method will throw a SpannerException with code ErrorCode#DEADLINE_EXCEEDED if a statement timeout has been set on this connection, and the commit operation takes longer than this timeout.

• Calling this method on a connection in autocommit mode and with no temporary transaction, will cause an exception
• Calling this method while a DDL batch is active will cause an exception
• Calling this method on a connection with a transaction that has not yet started, will end that transaction and any properties that might have been set on that transaction, and return the connection to its previous state. This means that if a transaction is created and set to read-only, and then committed before any statements have been executed, the read-only transaction is ended and any subsequent statements will be executed in a new transaction. If the connection is in read-write mode, the default for new transactions will be TransactionMode#READ_WRITE_TRANSACTION. Committing an empty transaction also does not generate a read timestamp or a commit timestamp, and calling one of the methods Connection#getReadTimestamp() or Connection#getCommitTimestamp() will cause an exception.
• Calling this method on a connection with a TransactionMode#READ_ONLY_TRANSACTION transaction will end that transaction. If the connection is in read-write mode, any subsequent transaction will by default be a TransactionMode#READ_WRITE_TRANSACTION transaction, unless any following transaction is explicitly set to TransactionMode#READ_ONLY_TRANSACTION
• Calling this method on a connection with a TransactionMode#READ_WRITE_TRANSACTION transaction will send all buffered mutations to the database, commit any DML statements that have been executed during this transaction and end the transaction.

Executes the given statement if allowed in the current TransactionMode and connection state. The returned value depends on the type of statement:

• Queries and DML statements with returning clause will return a ResultSet.
• Simple DML statements will return an update count
• DDL statements will return a ResultType#NO_RESULT
• Connection and transaction statements (SET AUTOCOMMIT=TRUE|FALSE, SHOW AUTOCOMMIT, SET TRANSACTION READ ONLY, etc) will return either a ResultSet or ResultType#NO_RESULT, depending on the type of statement (SHOW or SET)

Executes the given statement if allowed in the current TransactionMode and connection state, and if the result that would be returned is in the set of allowed result types. The statement will not be sent to Cloud Spanner if the result type would not be allowed. This method can be used by drivers that must limit the type of statements that are allowed for a given method, e.g. for the java.sql.Statement#executeQuery(String) and java.sql.Statement#executeUpdate(String) methods.

The returned value depends on the type of statement:

• Queries and DML statements with returning clause will return a ResultSet.
• Simple DML statements will return an update count
• DDL statements will return a ResultType#NO_RESULT
• Connection and transaction statements (SET AUTOCOMMIT=TRUE|FALSE, SHOW AUTOCOMMIT, SET TRANSACTION READ ONLY, etc) will return either a ResultSet or ResultType#NO_RESULT, depending on the type of statement (SHOW or SET)

Executes the given statement if allowed in the current TransactionMode and connection state asynchronously. The returned value depends on the type of statement:

• Queries and DML statements with returning clause will return an AsyncResultSet.
• Simple DML statements will return an ApiFuture with an update count that is done when the DML statement has been applied successfully, or that throws an ExecutionException if the DML statement failed.
• DDL statements will return an ApiFuture containing a Void that is done when the DDL statement has been applied successfully, or that throws an ExecutionException if the DDL statement failed.
• Connection and transaction statements (SET AUTOCOMMIT=TRUE|FALSE, SHOW AUTOCOMMIT, SET TRANSACTION READ ONLY, etc) will return either a ResultSet or ResultType#NO_RESULT, depending on the type of statement (SHOW or SET)

This method is guaranteed to be non-blocking.

Executes a list of DML statements (can be simple DML statements or DML statements with returning clause) in a single request. The statements will be executed in order and the semantics is the same as if each statement is executed by Connection#executeUpdate(Statement) in a loop. This method returns an array of long integers, each representing the number of rows modified by each statement.

If an individual statement fails, execution stops and a SpannerBatchUpdateException is returned, which includes the error and the number of rows affected by the statements that are run prior to the error.

For example, if statements contains 3 statements, and the 2nd one is not a valid DML. This method throws a SpannerBatchUpdateException that contains the error message from the 2nd statement, and an array of length 1 that contains the number of rows modified by the 1st statement. The 3rd statement will not run. Executes the given statements as DML statements in one batch. If one of the statements does not contain a valid DML statement, the method will throw a SpannerException.

Executes a list of DML statements (can be simple DML statements or DML statements with returning clause) in a single request. The statements will be executed in order and the semantics is the same as if each statement is executed by Connection#executeUpdate(Statement) in a loop. This method returns an ApiFuture that contains an array of long integers, each representing the number of rows modified by each statement.

This method is guaranteed to be non-blocking.

If an individual statement fails, execution stops and a SpannerBatchUpdateException is returned, which includes the error and the number of rows affected by the statements that are run prior to the error.

For example, if statements contains 3 statements, and the 2nd one is not a valid DML. This method throws a SpannerBatchUpdateException that contains the error message from the 2nd statement, and an array of length 1 that contains the number of rows modified by the 1st statement. The 3rd statement will not run. Executes the given statements as DML statements in one batch. If one of the statements does not contain a valid DML statement, the method will throw a SpannerException.

Executes the given statement (a query or a DML statement with returning clause) and returns the result as a ResultSet. This method blocks and waits for a response from Spanner. If the statement does not contain a valid query or a DML statement with returning clause, the method will throw a SpannerException.

Executes the given statement (a query or a DML statement with returning clause) asynchronously and returns the result as an AsyncResultSet. This method is guaranteed to be non-blocking. If the statement does not contain a valid query or a DML statement with returning clause, the method will throw a SpannerException.

See AsyncResultSet#setCallback(java.util.concurrent.Executor, com.google.cloud.spanner.AsyncResultSet.ReadyCallback) for more information on how to consume the results of the statement asynchronously.

It is also possible to consume the returned AsyncResultSet in the same way as a normal ResultSet, i.e. in a while-loop calling AsyncResultSet#next().

Executes the given statement as a simple DML statement. If the statement does not contain a valid DML statement, the method will throw a SpannerException.

Executes the given statement asynchronously as a simple DML statement. If the statement does not contain a simple DML statement, the method will throw a SpannerException. A DML statement with returning clause will throw a SpannerException.

This method is guaranteed to be non-blocking.

The DatabaseClient that is used by this Connection.

The Dialect that is used by this Connection.

Returns the DirectedReadOptions that are used for both single-use and multi-use read-only transactions on this connection.

Returns the maximum degree of parallelism that is used for #runPartitionedQuery(Statement, PartitionOptions, QueryOption...)

Gets the maximum number of partitions that should be included as a hint to Cloud Spanner when partitioning a query on this connection. Note that this is only a hint and Cloud Spanner might choose to ignore the hint.

Gets the current query optimizer statistics package of this connection.

Gets the current query optimizer version of this connection.

Gets the current RPC priority of this connection.

Returns the read timestamp of the current/last TransactionMode#READ_ONLY_TRANSACTION transaction, or the read timestamp of the last query in autocommit mode.

• When in autocommit mode: The method will return the read timestamp of the last statement if the last statement was a query.
• When in a TransactionMode#READ_ONLY_TRANSACTION transaction that has started (a query has been executed), or that has just committed: The read timestamp of the transaction. If the read-only transaction was committed without ever executing a query, calling this method after the commit will also throw a SpannerException
• In all other cases the method will throw a SpannerException.

Returns the current savepoint support for this connection.

Returns whether this connection will execute all queries as partitioned queries.

Returns whether data boost is enabled for partitioned queries. See also #partitionQuery(Statement, PartitionOptions, QueryOption...)

Partitions the given query, so it can be executed in parallel. This method returns a ResultSet with a string-representation of the partitions that were created. These strings can be used to execute a partition either on this connection or an any other connection (on this host or an any other host) by calling the method #runPartition(String). This method will automatically enable data boost for the query if #isDataBoostEnabled() returns true.

Releases the savepoint with the given name. The savepoint and all later savepoints will be removed from the current transaction and can no longer be used.

Removes one existing TransactionRetryListener from this Connection, if it is present (optional operation).

Rollbacks the current transaction of this connection. All mutations or DDL statements that have been buffered during the current transaction will be removed from the buffer.

If the connection is in autocommit mode, and there is a temporary transaction active on this connection, calling this method will cause the connection to go back to autocommit mode after calling this method.

• Calling this method on a connection in autocommit mode and with no temporary transaction will cause an exception
• Calling this method while a DDL batch is active will cause an exception
• Calling this method on a connection with a transaction that has not yet started, will end that transaction and any properties that might have been set on that transaction, and return the connection to its previous state. This means that if a transaction is created and set to read-only, and then rolled back before any statements have been executed, the read-only transaction is ended and any subsequent statements will be executed in a new transaction. If the connection is in read-write mode, the default for new transactions will be TransactionMode#READ_WRITE_TRANSACTION.
• Calling this method on a connection with a TransactionMode#READ_ONLY_TRANSACTION transaction will end that transaction. If the connection is in read-write mode, any subsequent transaction will by default be a TransactionMode#READ_WRITE_TRANSACTION transaction, unless any following transaction is explicitly set to TransactionMode#READ_ONLY_TRANSACTION
• Calling this method on a connection with a TransactionMode#READ_WRITE_TRANSACTION transaction will clear all buffered mutations, rollback any DML statements that have been executed during this transaction and end the transaction.

Rollbacks the current transaction of this connection. All mutations or DDL statements that have been buffered during the current transaction will be removed from the buffer.

This method is guaranteed to be non-blocking. The returned ApiFuture will be done when the transaction has been rolled back.

If the connection is in autocommit mode, and there is a temporary transaction active on this connection, calling this method will cause the connection to go back to autocommit mode after calling this method.

• Calling this method on a connection in autocommit mode and with no temporary transaction will cause an exception
• Calling this method while a DDL batch is active will cause an exception
• Calling this method on a connection with a transaction that has not yet started, will end that transaction and any properties that might have been set on that transaction, and return the connection to its previous state. This means that if a transaction is created and set to read-only, and then rolled back before any statements have been executed, the read-only transaction is ended and any subsequent statements will be executed in a new transaction. If the connection is in read-write mode, the default for new transactions will be TransactionMode#READ_WRITE_TRANSACTION.
• Calling this method on a connection with a TransactionMode#READ_ONLY_TRANSACTION transaction will end that transaction. If the connection is in read-write mode, any subsequent transaction will by default be a TransactionMode#READ_WRITE_TRANSACTION transaction, unless any following transaction is explicitly set to TransactionMode#READ_ONLY_TRANSACTION
• Calling this method on a connection with a TransactionMode#READ_WRITE_TRANSACTION transaction will clear all buffered mutations, rollback any DML statements that have been executed during this transaction and end the transaction.

Rolls back to the given savepoint. Rolling back to a savepoint undoes all changes and releases all internal locks that have been taken by the transaction after the savepoint. Rolling back to a savepoint does not remove the savepoint from the transaction, and it is possible to roll back to the same savepoint multiple times. All savepoints that have been defined after the given savepoint are removed from the transaction.

Sends all buffered DML or DDL statements of the current batch to the database, waits for these to be executed and ends the current batch. The method will throw an exception for the first statement that cannot be executed, or return successfully if all statements could be executed. If an exception is thrown for a statement in the batch, the preceding statements in the same batch may still have been applied to the database.

This method may only be called when a (possibly empty) batch is active.

Sends all buffered DML or DDL statements of the current batch to the database, waits for these to be executed and ends the current batch. The method will throw an exception for the first statement that cannot be executed, or return successfully if all statements could be executed. If an exception is thrown for a statement in the batch, the preceding statements in the same batch may still have been applied to the database.

This method is guaranteed to be non-blocking. The returned ApiFuture will be done when the batch has been successfully applied, or when one or more of the statements in the batch has failed and the further execution of the batch has been halted.

This method may only be called when a (possibly empty) batch is active.

Executes the given partition of a query. The encodedPartitionId should be a string that was returned by #partitionQuery(Statement, PartitionOptions, QueryOption...).

Executes the given query as a partitioned query. The query will first be partitioned using the #partitionQuery(Statement, PartitionOptions, QueryOption...) method. Each of the partitions will then be executed in the background, and the results will be merged into a single result set.

This method will use maxPartitionedParallelism threads to execute the partitioned query. Set this variable to a higher/lower value to increase/decrease the degree of parallelism used for execution.

Creates a savepoint with the given name.

The uniqueness constraints on a savepoint name depends on the database dialect that is used:

• Dialect#GOOGLE_STANDARD_SQL requires that savepoint names are unique within a transaction. The name of a savepoint that has been released or destroyed because the transaction has rolled back to a savepoint that was defined before that savepoint can be re-used within the transaction.
• Dialect#POSTGRESQL follows the rules for savepoint names in PostgreSQL. This means that multiple savepoints in one transaction can have the same name, but only the last savepoint with a given name is visible. See PostgreSQL savepoint documentation for more information.

Sets whether this connection should always use partitioned queries when a query is executed on this connection. Setting this flag to true and then executing a query that cannot be partitioned, or executing a query in a read/write transaction, will cause an error. Use this flag in combination with #setDataBoostEnabled(boolean) to force all queries on this connection to use data boost.

Sets autocommit on/off for this Connection. Connections in autocommit mode will apply any changes to the database directly without waiting for an explicit commit. DDL- and DML statements as well as Mutations are sent directly to Spanner, and committed automatically unless the statement caused an error. The statement is retried in case of an AbortedException. All other errors will cause the underlying transaction to be rolled back.

A Connection that is in autocommit and read/write mode will allow all types of statements: Queries, DML, DDL, and Mutations (writes). If the connection is in read-only mode, only queries will be allowed.

Connections in autocommit mode may also accept partitioned DML statements. See Connection#setAutocommitDmlMode(AutocommitDmlMode) for more information.

Sets the mode for executing DML statements in autocommit mode for this connection. This setting is only used when the connection is in autocommit mode, and may only be set while the transaction is in autocommit mode and not in a temporary transaction. The autocommit transaction mode is reset to its default value of AutocommitDmlMode#TRANSACTIONAL when autocommit mode is changed on the connection.

Enable data boost for partitioned queries. See also #partitionQuery(Statement, PartitionOptions, QueryOption...)

Sets whether this connection should delay the actual start of a read/write transaction until the first write operation is observed on that transaction. All read operations that are executed before the first write operation in the transaction will be executed as if the connection was in auto-commit mode. This can reduce locking, especially for transactions that execute a large number of reads before any writes, at the expense of a lower transaction isolation.

NOTE: This will make read/write transactions non-serializable.

Sets the DirectedReadOptions to use for both single-use and multi-use read-only transactions on this connection.

Sets the maximum degree of parallelism that is used when executing a partitioned query using #runPartitionedQuery(Statement, PartitionOptions, QueryOption...). The method will use up to maxThreads to execute and retrieve the results from Cloud Spanner. Set this value to 0> to use the number of available processors as returned by Runtime#availableProcessors().

Sets the maximum number of partitions that should be included as a hint to Cloud Spanner when partitioning a query on this connection. Note that this is only a hint and Cloud Spanner might choose to ignore the hint.

Sets the query optimizer statistics package

Sets the query optimizer version to use for this connection.

Sets the priority to use for RPCs executed by this connection..

Sets this connection to read-only or read-write. This method may only be called when no transaction is active. A connection that is in read-only mode, will never allow any kind of changes to the database to be submitted.

Sets the staleness to use for the current read-only transaction. This method may only be called when the transaction mode of the current transaction is TransactionMode#READ_ONLY_TRANSACTION and there is no transaction that has started, or when the connection is in read-only and autocommit mode.

Sets whether this connection will internally retry read/write transactions that abort. The default is true. When internal retry is enabled, the Connection will keep track of a running SHA256 checksum of all ResultSets that have been returned from Cloud Spanner. If the checksum that is calculated during an internal retry differs from the original checksum, the transaction will abort with an AbortedDueToConcurrentModificationException.

Note that retries of a read/write transaction that calls a non-deterministic function on Cloud Spanner, such as CURRENT_TIMESTAMP(), will never be successful, as the data returned during the retry will always be different from the original transaction.

It is also highly recommended that all queries in a read/write transaction have an ORDER BY clause that guarantees that the data is returned in the same order as in the original transaction if the transaction is internally retried. The most efficient way to achieve this is to always include the primary key columns at the end of the ORDER BY clause.

This method may only be called when the connection is in read/write transactional mode and no transaction has been started yet.

Sets whether this connection should request commit statistics from Cloud Spanner for read/write transactions and DML statements in autocommit mode.

Sets how savepoints should be supported on this connection.

Sets the statement tag to use for the next statement that is executed. The tag is automatically cleared after the statement is executed. Statement tags can be used both with autocommit=true and autocommit=false, and can be used for partitioned DML.

Statement tags are not allowed before COMMIT and ROLLBACK statements.

Statement tags are allowed before START BATCH DML statements and will be included in the ExecuteBatchDmlRequest that is sent to Spanner. Statement tags are not allowed inside a batch.

Sets the duration the connection should wait before automatically aborting the execution of a statement. The default is no timeout. Statement timeouts are applied all types of statements, both in autocommit and transactional mode. They also apply to Connection#commit() and Connection#rollback() statements.

A DML statement in autocommit mode may or may not have actually been applied to the database, depending on when the timeout occurred.

A DML statement in a transaction that times out may still have been applied to the transaction. If you still decide to commit the transaction after such a timeout, the DML statement may or may not have been part of the transaction, depending on whether the timeout occurred before or after the statement was (successfully) sent to Spanner. You should therefore either always rollback a transaction that had a DML statement that timed out, or you should accept that the timed out statement still might have been applied to the database.

DDL statements and DML statements in AutocommitDmlMode#PARTITIONED_NON_ATOMIC mode cannot be rolled back. If such a statement times out, it may or may not have been applied to the database. The same applies to commit and rollback statements.

Statements that time out will throw a SpannerException with error code ErrorCode#DEADLINE_EXCEEDED.

Sets the transaction mode to use for current transaction. This method may only be called when in a transaction, and before the transaction is actually started, i.e. before any statements have been executed in the transaction.

Sets the transaction tag to use for the current transaction. This method may only be called when in a transaction and before any statements have been executed in the transaction.

The tag will be set as the transaction tag of all statements during the transaction, and as the transaction tag of the commit.

The transaction tag will automatically be cleared after the transaction has ended.

Starts a new DDL batch on this connection. A DDL batch allows several DDL statements to be grouped into a batch that can be executed as a group. DDL statements that are issued during the batch are buffered locally and will return immediately with an OK. It is not guaranteed that a DDL statement that has been issued during a batch will eventually succeed when running the batch. Aborting a DDL batch will clear the DDL buffer and will have made no changes to the database. Running a DDL batch will send all buffered DDL statements to Spanner, and Spanner will try to execute these. The result will be OK if all the statements executed successfully. If a statement cannot be executed, Spanner will stop execution at that point and return an error message for the statement that could not be executed. Preceding statements of the batch may have been executed.

This method may only be called when the connection is in read/write mode, autocommit mode is enabled or no read/write transaction has been started, and there is not already another batch active. The connection will only accept DDL statements while a DDL batch is active.

Starts a new DML batch on this connection. A DML batch allows several DML statements to be grouped into a batch that can be executed as a group. DML statements that are issued during the batch are buffered locally and will return immediately with an OK. It is not guaranteed that a DML statement that has been issued during a batch will eventually succeed when running the batch. Aborting a DML batch will clear the DML buffer and will have made no changes to the database. Running a DML batch will send all buffered DML statements to Spanner, and Spanner will try to execute these. The result will be OK if all the statements executed successfully. If a statement cannot be executed, Spanner will stop execution at that point and return SpannerBatchUpdateException for the statement that could not be executed. Preceding statements of the batch will have been executed, and the update counts of those statements can be retrieved through SpannerBatchUpdateException#getUpdateCounts().

This method may only be called when the connection is in read/write mode, autocommit mode is enabled or no read/write transaction has been started, and there is not already another batch active. The connection will only accept DML statements while a DML batch is active.

Writes the specified mutation directly to the database and commits the change. The value is readable after the successful completion of this method. Writing multiple mutations to a database by calling this method multiple times mode is inefficient, as each call will need a round trip to the database. Instead, you should consider writing the mutations together by calling Connection#write(Iterable).

Calling this method is only allowed in autocommit mode. See Connection#bufferedWrite(Iterable) for writing mutations in transactions.

Writes the specified mutations directly to the database and commits the changes. The values are readable after the successful completion of this method.

Calling this method is only allowed in autocommit mode. See Connection#bufferedWrite(Iterable) for writing mutations in transactions.

Writes the specified mutation directly to the database and commits the change. The value is readable after the successful completion of the returned ApiFuture. Writing multiple mutations to a database by calling this method multiple times mode is inefficient, as each call will need a round trip to the database. Instead, you should consider writing the mutations together by calling Connection#writeAsync(Iterable).

This method is guaranteed to be non-blocking.

Calling this method is only allowed in autocommit mode. See Connection#bufferedWrite(Iterable) for writing mutations in transactions.

Writes the specified mutations directly to the database and commits the changes. The values are readable after the successful completion of the returned ApiFuture.

This method is guaranteed to be non-blocking.

Calling this method is only allowed in autocommit mode. See Connection#bufferedWrite(Iterable) for writing mutations in transactions.