org.apache.flink.table.connector.source.abilities

Interface SupportsRowLevelModificationScan

@PublicEvolving
public interface SupportsRowLevelModificationScan

Interface for ScanTableSources that support the row-level modification. The table source is responsible for returning the information described by RowLevelModificationScanContext. The context will be propagated to the sink which implements SupportsRowLevelUpdate or SupportsRowLevelDelete.

Note: This interface is optional for table sources to implement. For cases where the table source neither needs to know the type of row-level modification nor propagate information to sink, the table source doesn't need to implement this interface. See more details at applyRowLevelModificationScan(RowLevelModificationType, RowLevelModificationScanContext).

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	SupportsRowLevelModificationScan.RowLevelModificationType Type of the row-level modification for table.

Method Summary

Modifier and Type	Method and Description
RowLevelModificationScanContext	applyRowLevelModificationScan(SupportsRowLevelModificationScan.RowLevelModificationType rowLevelModificationType, RowLevelModificationScanContext previousContext) Applies the type of row-level modification and the previous RowLevelModificationScanContext returned by previous table source scan, return a new RowLevelModificationScanContext.

Method Detail

applyRowLevelModificationScan

RowLevelModificationScanContext applyRowLevelModificationScan(SupportsRowLevelModificationScan.RowLevelModificationType rowLevelModificationType,
                                                              @Nullable
                                                              RowLevelModificationScanContext previousContext)

Applies the type of row-level modification and the previous RowLevelModificationScanContext returned by previous table source scan, return a new RowLevelModificationScanContext. If the table source is the last one, the RowLevelModificationScanContext will be passed to the table sink. Otherwise, it will be passed to the following table source.

Note: For the all tables in the UPDATE/DELETE statement, this method will be involved for the corresponding table source scan.

Note: It may have multiple table sources in the case of sub-query. In such case, it will return multiple RowLevelModificationScanContexts. To handle such case, the planner will also pass the previous RowLevelModificationScanContext to the current table source scan which is expected to decide what to do with the previous RowLevelModificationScanContext. The order is consistent with the compilation order of the table sources. The planer will only pass the last context returned to the sink.

Parameters:

previousContext - the context returned by previous table source, if there's no previous context, it'll be null.