Class BaseScanTaskGroup<T extends ScanTask>

    • Constructor Detail

      • BaseScanTaskGroup

        public BaseScanTaskGroup​(StructLike groupingKey,
                                 java.util.Collection<T> tasks)
      • BaseScanTaskGroup

        public BaseScanTaskGroup​(java.util.Collection<T> tasks)
    • Method Detail

      • groupingKey

        public StructLike groupingKey()
        Description copied from interface: ScanTaskGroup
        Returns a grouping key for this task group.

        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.

        Specified by:
        groupingKey in interface ScanTaskGroup<T extends ScanTask>
        a grouping key for this task group
      • toString

        public java.lang.String toString()
        toString in class java.lang.Object