@Experimental
public interface PartitionableTableSource
TableSource.
A PartitionableTableSource can exclude partitions from reading, which
includes skipping the metadata. This is especially useful when there are thousands
of partitions in a table.
A partition is represented as a Map<String, String> which maps from partition
field name to partition value. Since the map is NOT ordered, the correct order of partition
fields should be obtained via partition keys of catalog table.
| 限定符和类型 | 方法和说明 |
|---|---|
TableSource |
applyPartitionPruning(List<Map<String,String>> remainingPartitions)
Applies the remaining partitions to the table source.
|
List<Map<String,String>> |
getPartitions()
Returns all the partitions of this
PartitionableTableSource. |
List<Map<String,String>> getPartitions()
PartitionableTableSource.TableSource applyPartitionPruning(List<Map<String,String>> remainingPartitions)
remainingPartitions is
the remaining partitions of getPartitions() after partition pruning applied.
After trying to apply partition pruning, we should return a new TableSource
instance which holds all pruned-partitions.
remainingPartitions - Remaining partitions after partition pruning applied.TableSource holds all pruned-partitions.Copyright © 2014–2020 The Apache Software Foundation. All rights reserved.