Interface Connector

public interface Connector

Method Summary

Modifier and Type	Method	Description
default ConnectorTransactionHandle	beginTransaction(IsolationLevel isolationLevel, boolean readOnly, boolean autoCommit)	Start a new transaction and return a handle for it.
default void	commit(ConnectorTransactionHandle transactionHandle)	Commit the transaction.
default ConnectorAccessControl	getAccessControl()
default List<PropertyMetadata<?>>	getAnalyzeProperties()
default Set<ConnectorCapabilities>	getCapabilities()
default List<PropertyMetadata<?>>	getColumnProperties()
default Iterable<EventListener>	getEventListeners()
default Optional<FunctionProvider>	getFunctionProvider()
default ConnectorIndexProvider	getIndexProvider()
default long	getInitialMemoryRequirement()	Retrieves the initial memory requirement for the connector.
default List<PropertyMetadata<?>>	getMaterializedViewProperties()
default ConnectorMetadata	getMetadata(ConnectorSession session, ConnectorTransactionHandle transactionHandle)	Guaranteed to be called at most once per transaction.
default ConnectorNodePartitioningProvider	getNodePartitioningProvider()
default ConnectorPageSinkProvider	getPageSinkProvider()
default ConnectorPageSourceProvider	getPageSourceProvider()
default ConnectorPageSourceProviderFactory	getPageSourceProviderFactory()	Provide a pageSourceProviderFactory to create stateful instances of PageSourceProvider per query.
default Set<io.trino.spi.procedure.Procedure>	getProcedures()
default ConnectorRecordSetProvider	getRecordSetProvider()
default List<PropertyMetadata<?>>	getSchemaProperties()
default List<PropertyMetadata<?>>	getSessionProperties()
default ConnectorSplitManager	getSplitManager()
default Set<SystemTable>	getSystemTables()
default Set<ConnectorTableFunction>	getTableFunctions()
default Set<TableProcedureMetadata>	getTableProcedures()
default List<PropertyMetadata<?>>	getTableProperties()
default List<PropertyMetadata<?>>	getViewProperties()
default boolean	isSingleStatementWritesOnly()	True if the connector only supports write statements in independent transactions.
default void	rollback(ConnectorTransactionHandle transactionHandle)	Rollback the transaction.
default void	shutdown()	Shutdown the connector by releasing any held resources such as threads, sockets, etc.

Method Details

beginTransaction

default ConnectorTransactionHandle beginTransaction(IsolationLevel isolationLevel,
 boolean readOnly,
 boolean autoCommit)

Start a new transaction and return a handle for it. The engine will call getMetadata(io.trino.spi.connector.ConnectorSession, io.trino.spi.connector.ConnectorTransactionHandle) to fetch the metadata instance for the transaction. The engine will later call exactly one of commit(io.trino.spi.connector.ConnectorTransactionHandle) or rollback(io.trino.spi.connector.ConnectorTransactionHandle) to end the transaction, even in auto-commit mode.

If true is returned from isSingleStatementWritesOnly(), then the engine will enforce that auto-commit mode is used for writes, allowing connectors to execute writes immediately, rather than needing to wait until the transaction is committed.

Parameters:

isolationLevel - minimum isolation level for the transaction

readOnly - if the transaction is guaranteed to only read data (not write)

autoCommit - if the transaction uses auto-commit mode

getMetadata

default ConnectorMetadata getMetadata(ConnectorSession session,
 ConnectorTransactionHandle transactionHandle)

Guaranteed to be called at most once per transaction. The returned metadata will only be accessed in a single threaded context.

getSplitManager

default ConnectorSplitManager getSplitManager()

Throws:

UnsupportedOperationException - if this connector does not support tables with splits

getPageSourceProvider

default ConnectorPageSourceProvider getPageSourceProvider()

Throws:

UnsupportedOperationException - if this connector does not support reading tables page at a time

getPageSourceProviderFactory

default ConnectorPageSourceProviderFactory getPageSourceProviderFactory()

Provide a pageSourceProviderFactory to create stateful instances of PageSourceProvider per query. If not implemented a singleton instance returned by getPageSourceProvider will be used for all queries.

getRecordSetProvider

default ConnectorRecordSetProvider getRecordSetProvider()

Throws:

UnsupportedOperationException - if this connector does not support reading tables record at a time

getPageSinkProvider

default ConnectorPageSinkProvider getPageSinkProvider()

Throws:

UnsupportedOperationException - if this connector does not support writing tables page at a time

getIndexProvider

default ConnectorIndexProvider getIndexProvider()

Throws:

UnsupportedOperationException - if this connector does not support indexes

getNodePartitioningProvider

default ConnectorNodePartitioningProvider getNodePartitioningProvider()

Throws:

UnsupportedOperationException - if this connector does not support partitioned table layouts

getSystemTables

default Set<SystemTable> getSystemTables()

Returns:

the set of system tables provided by this connector

getFunctionProvider

@Experimental(eta="2022-10-31")
default Optional<FunctionProvider> getFunctionProvider()

Returns:

the set of procedures provided by this connector

getProcedures

default Set<io.trino.spi.procedure.Procedure> getProcedures()

Returns:

the set of procedures provided by this connector

getTableProcedures

default Set<TableProcedureMetadata> getTableProcedures()

getInitialMemoryRequirement

default long getInitialMemoryRequirement()

Retrieves the initial memory requirement for the connector.

The memory allocation is per catalog and is freed when the catalog is shut down.

Returns:

the initial memory requirement in bytes.

getTableFunctions

default Set<ConnectorTableFunction> getTableFunctions()

Returns:

the set of table functions provided by this connector

getSessionProperties

default List<PropertyMetadata<?>> getSessionProperties()

Returns:

the system properties for this connector

getSchemaProperties

default List<PropertyMetadata<?>> getSchemaProperties()

Returns:

the schema properties for this connector

getAnalyzeProperties

default List<PropertyMetadata<?>> getAnalyzeProperties()

Returns:

the analyze properties for this connector

getTableProperties

default List<PropertyMetadata<?>> getTableProperties()

Returns:

the table properties for this connector

getViewProperties

default List<PropertyMetadata<?>> getViewProperties()

Returns:

the view properties for this connector

getMaterializedViewProperties

default List<PropertyMetadata<?>> getMaterializedViewProperties()

Returns:

the materialized view properties for this connector

getColumnProperties

default List<PropertyMetadata<?>> getColumnProperties()

Returns:

the column properties for this connector

getAccessControl

default ConnectorAccessControl getAccessControl()

Throws:

UnsupportedOperationException - if this connector does not have an access control

getEventListeners

default Iterable<EventListener> getEventListeners()

Returns:

the event listeners provided by this connector

commit

default void commit(ConnectorTransactionHandle transactionHandle)

Commit the transaction. Will be called at most once and will not be called if rollback(io.trino.spi.connector.ConnectorTransactionHandle) is called.

rollback

default void rollback(ConnectorTransactionHandle transactionHandle)

Rollback the transaction. Will be called at most once and will not be called if commit(io.trino.spi.connector.ConnectorTransactionHandle) is called.

Note: calls to this method may race with calls to the ConnectorMetadata.

isSingleStatementWritesOnly

default boolean isSingleStatementWritesOnly()

True if the connector only supports write statements in independent transactions. The engine will enforce this for the connector by requiring auto-commit mode for writes.

shutdown

default void shutdown()

Shutdown the connector by releasing any held resources such as threads, sockets, etc. This method will only be called when no queries are using the connector. After this method is called, no methods will be called on the connector or any objects that have been returned from the connector.

getCapabilities

default Set<ConnectorCapabilities> getCapabilities()