Package org.apache.druid.segment

Class DoubleDimensionIndexer

java.lang.Object
org.apache.druid.segment.DoubleDimensionIndexer
All Implemented Interfaces:
DimensionIndexer<Double,Double,Double>
public class DoubleDimensionIndexer extends Object implements DimensionIndexer<Double,Double,Double>

  • Field Details

  • Constructor Details

    • DoubleDimensionIndexer

      public DoubleDimensionIndexer(String dimensionName)

  • Method Details

    • processRowValsToUnsortedEncodedKeyComponent

      public EncodedKeyComponent<Double> processRowValsToUnsortedEncodedKeyComponent(@Nullable Object dimValues, boolean reportParseExceptions)
      Description copied from interface: DimensionIndexer
      Encodes the given row value(s) of the dimension to be used within a row key. It also updates the internal state of the DimensionIndexer, e.g. the dimLookup.

      For example, the dictionary-encoded String-type column will return an int[] containing dictionary IDs.

      Specified by:
      processRowValsToUnsortedEncodedKeyComponent in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      dimValues - Value(s) of the dimension in a row. This can either be a single value or a list of values (for multi-valued dimensions)
      reportParseExceptions - true if parse exceptions should be reported, false otherwise
      Returns:
      Encoded dimension value(s) to be used as a component for the row key. Contains an object of the DimensionIndexer and the effective size of the key component in bytes.

    • setSparseIndexed

      public void setSparseIndexed()
      Description copied from interface: DimensionIndexer
      This method will be called while building an IncrementalIndex whenever a known dimension column (either through an explicit schema on the ingestion spec, or auto-discovered while processing rows) is absent in any row that is processed, to allow an indexer to account for any missing rows if necessary. Useful so that a string DimensionSelector built on top of an IncrementalIndex may accurately report DimensionDictionarySelector.nameLookupPossibleInAdvance() by allowing it to track if it has any implicit null valued rows. At index persist/merge time all missing columns for a row will be explicitly replaced with the value appropriate null or default value.
      Specified by:
      setSparseIndexed in interface DimensionIndexer<Double,Double,Double>

    • getUnsortedEncodedValueFromSorted

      public Double getUnsortedEncodedValueFromSorted(Double sortedIntermediateValue)
      Description copied from interface: DimensionIndexer
      Given an encoded value that was ordered by associated actual value, return the equivalent encoded value ordered by time of ingestion. Using the example in the class description: getUnsortedEncodedValueFromSorted(2) would return 0
      Specified by:
      getUnsortedEncodedValueFromSorted in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      sortedIntermediateValue - value to convert
      Returns:
      converted value

    • getSortedIndexedValues

      public CloseableIndexed<Double> getSortedIndexedValues()
      Description copied from interface: DimensionIndexer
      Returns an indexed structure of this dimension's sorted actual values. The integer IDs represent the ordering of the sorted values. Using the example in the class description: "Apple"=0, "Hello"=1, "World"=2
      Specified by:
      getSortedIndexedValues in interface DimensionIndexer<Double,Double,Double>
      Returns:
      Sorted index of actual values

    • getMinValue

      public Double getMinValue()
      Description copied from interface: DimensionIndexer
      Get the minimum dimension value seen by this indexer. NOTE: On an in-memory segment (IncrementalIndex), we can determine min/max values by looking at the stream of row values seen in calls to processSingleRowValToIndexKey(). However, on a disk-backed segment (QueryableIndex), the numeric dimensions do not currently have any supporting index structures that can be used to efficiently determine min/max values. When numeric dimension support is added, the segment format should be changed to store min/max values, to avoid performing a full-column scan to determine these values for numeric dims.
      Specified by:
      getMinValue in interface DimensionIndexer<Double,Double,Double>
      Returns:
      min value

    • getMaxValue

      public Double getMaxValue()
      Description copied from interface: DimensionIndexer
      Get the maximum dimension value seen by this indexer.
      Specified by:
      getMaxValue in interface DimensionIndexer<Double,Double,Double>
      Returns:
      max value

    • getCardinality

      public int getCardinality()
      Description copied from interface: DimensionIndexer
      Get the cardinality of this dimension's values.
      Specified by:
      getCardinality in interface DimensionIndexer<Double,Double,Double>
      Returns:
      value cardinality

    • getColumnCapabilities

      public ColumnCapabilities getColumnCapabilities()
      Specified by:
      getColumnCapabilities in interface DimensionIndexer<Double,Double,Double>

    • makeDimensionSelector

      public DimensionSelector makeDimensionSelector(DimensionSpec spec, IncrementalIndexRowHolder currEntry, IncrementalIndex.DimensionDesc desc)
      Description copied from interface: DimensionIndexer
      Return an object used to read values from this indexer's column as Strings.
      Specified by:
      makeDimensionSelector in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      spec - Specifies the output name of a dimension and any extraction functions to be applied.
      currEntry - Provides access to the current Row object in the Cursor
      desc - Descriptor object for this dimension within an IncrementalIndex
      Returns:
      A new object that reads rows from currEntry

    • makeColumnValueSelector

      public ColumnValueSelector<?> makeColumnValueSelector(IncrementalIndexRowHolder currEntry, IncrementalIndex.DimensionDesc desc)
      Description copied from interface: DimensionIndexer
      Return an object used to read values from this indexer's column.
      Specified by:
      makeColumnValueSelector in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      currEntry - Provides access to the current Row object in the Cursor
      desc - Descriptor object for this dimension within an IncrementalIndex
      Returns:
      A new object that reads rows from currEntry

    • compareUnsortedEncodedKeyComponents

      public int compareUnsortedEncodedKeyComponents(@Nullable Double lhs, @Nullable Double rhs)
      Description copied from interface: DimensionIndexer
      Compares the row values for this DimensionIndexer's dimension from a Row key. The dimension value arrays within a Row key always use the "unsorted" ordering for encoded values. The row values are passed to this function as an Object, the implementer should cast them to the type appropriate for this dimension. For example, a dictionary encoded String implementation would cast the Objects as int[] arrays. When comparing, if the two arrays have different lengths, the shorter array should be ordered first. Otherwise, the implementer of this function should iterate through the unsorted encoded values, converting them to their actual type (e.g., performing a dictionary lookup for a dict-encoded String dimension), and comparing the actual values until a difference is found. Refer to StringDimensionIndexer.compareUnsortedEncodedKeyComponents() for a reference implementation. The comparison rules used by this method should match the rules used by DimensionHandler.getEncodedValueSelectorComparator(), otherwise incorrect ordering/merging of rows can occur during ingestion, causing issues such as imperfect rollup.
      Specified by:
      compareUnsortedEncodedKeyComponents in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      lhs - dimension value array from a Row key
      rhs - dimension value array from a Row key
      Returns:
      comparison of the two arrays

    • checkUnsortedEncodedKeyComponentsEqual

      public boolean checkUnsortedEncodedKeyComponentsEqual(@Nullable Double lhs, @Nullable Double rhs)
      Description copied from interface: DimensionIndexer
      Check if two row value arrays from Row keys are equal.
      Specified by:
      checkUnsortedEncodedKeyComponentsEqual in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      lhs - dimension value array from a Row key
      rhs - dimension value array from a Row key
      Returns:
      true if the two arrays are equal

    • getUnsortedEncodedKeyComponentHashCode

      public int getUnsortedEncodedKeyComponentHashCode(@Nullable Double key)
      Description copied from interface: DimensionIndexer
      Given a row value array from a Row key, generate a hashcode.
      Specified by:
      getUnsortedEncodedKeyComponentHashCode in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      key - dimension value array from a Row key
      Returns:
      hashcode of the array

    • convertUnsortedEncodedKeyComponentToActualList

      public Object convertUnsortedEncodedKeyComponentToActualList(Double key)
      Description copied from interface: DimensionIndexer
      Given a row value array from a Row key, as described in the documentation for DimensionIndexer.compareUnsortedEncodedKeyComponents(EncodedKeyComponentType, EncodedKeyComponentType), convert the unsorted encoded values to a list of actual values. If the key has one element, this method should return a single Object instead of a list.
      Specified by:
      convertUnsortedEncodedKeyComponentToActualList in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      key - dimension value array from a Row key
      Returns:
      single value or list containing the actual values corresponding to the encoded values in the input array

    • convertUnsortedValuesToSorted

      public ColumnValueSelector convertUnsortedValuesToSorted(ColumnValueSelector selectorWithUnsortedValues)
      Description copied from interface: DimensionIndexer
      Converts dictionary-encoded row values from unspecified (random) encoding order, to sorted encoding. This step is needed to be able to correctly map per-segment encoded values to global values on the next conversion step, DimensionMerger.convertSortedSegmentRowValuesToMergedRowValues(int, org.apache.druid.segment.ColumnValueSelector). The latter method requires sorted encoding values on the input, because DimensionMerger.writeMergedValueDictionary(java.util.List<org.apache.druid.segment.IndexableAdapter>) takes sorted lookups as it's input. For columns which do not use the DimensionMerger to merge dictionary encoded values, this method should provide a selector which is compatible with the expectations of DimensionMerger.processMergedRow(ColumnValueSelector), which might simply be to pass-through the 'unsorted' selector.
      Specified by:
      convertUnsortedValuesToSorted in interface DimensionIndexer<Double,Double,Double>

    • fillBitmapsFromUnsortedEncodedKeyComponent

      public void fillBitmapsFromUnsortedEncodedKeyComponent(Double key, int rowNum, MutableBitmap[] bitmapIndexes, BitmapFactory factory)
      Description copied from interface: DimensionIndexer
      Helper function for building bitmap indexes for integer-encoded dimensions. Called by IncrementalIndexAdapter as it iterates through its sequence of rows. Given a row value array from a Row key, with the current row number indicated by "rowNum", set the index for "rowNum" in the bitmap index for each value that appears in the row value array. For example, if key is an int[] array with values [1,3,4] for a dictionary-encoded String dimension, and rowNum is 27, this function would set bit 27 in bitmapIndexes[1], bitmapIndexes[3], and bitmapIndexes[4] See StringDimensionIndexer.fillBitmapsFromUnsortedEncodedKeyComponent() for a reference implementation. If a dimension type does not support bitmap indexes, this function will not be called and can be left unimplemented.
      Specified by:
      fillBitmapsFromUnsortedEncodedKeyComponent in interface DimensionIndexer<Double,Double,Double>
      Parameters:
      key - dimension value array from a Row key
      rowNum - current row number
      bitmapIndexes - array of bitmaps, indexed by integer dimension value
      factory - bitmap factory