public class BaseScanTaskGroup<T extends ScanTask> extends java.lang.Object implements ScanTaskGroup<T>
Constructor and Description |
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BaseScanTaskGroup(java.util.Collection<T> tasks) |
BaseScanTaskGroup(StructLike groupingKey,
java.util.Collection<T> tasks) |
Modifier and Type | Method and Description |
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StructLike |
groupingKey()
Returns a grouping key for this task group.
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java.util.Collection<T> |
tasks()
Returns scan tasks in this group.
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java.lang.String |
toString() |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
estimatedRowsCount, filesCount, sizeBytes
asCombinedScanTask, asDataTask, asFileScanTask, isDataTask, isFileScanTask
public BaseScanTaskGroup(StructLike groupingKey, java.util.Collection<T> tasks)
public BaseScanTaskGroup(java.util.Collection<T> tasks)
public StructLike groupingKey()
ScanTaskGroup
A grouping key is a set of values that are common amongst all rows produced by the tasks in this task group. The values may be the result of transforming the underlying data. For example, a grouping key can consist of a bucket ordinal computed by applying a bucket transform to a column of the underlying rows. The grouping key type is determined at planning time and is identical across all task groups produced by a scan.
Implementations should return an empty struct if the data grouping is random or unknown.
groupingKey
in interface ScanTaskGroup<T extends ScanTask>
public java.util.Collection<T> tasks()
ScanTaskGroup
tasks
in interface ScanTaskGroup<T extends ScanTask>
public java.lang.String toString()
toString
in class java.lang.Object