Interface ClusteringIndexFilter

  • All Known Implementing Classes:
    AbstractClusteringIndexFilter, ClusteringIndexNamesFilter, ClusteringIndexSliceFilter

    public interface ClusteringIndexFilter
    A filter that selects a subset of the rows of a given partition by using the "clustering index".

    In CQL terms, this correspond to the clustering columns selection and correspond to what the storage engine can do without filtering (and without 2ndary indexes). This does not include the restrictions on non-PK columns which can be found in RowFilter.

    • Method Detail

      • isReversed

        boolean isReversed()
        Whether the filter query rows in reversed clustering order or not.
        Returns:
        whether the filter query rows in reversed clustering order or not.
      • forPaging

        ClusteringIndexFilter forPaging​(ClusteringComparator comparator,
                                        Clustering<?> lastReturned,
                                        boolean inclusive)
        Returns a filter for continuing the paging of this filter given the last returned clustering prefix.
        Parameters:
        comparator - the comparator for the table this is a filter for.
        lastReturned - the last clustering that was returned for the query we are paging for. The resulting filter will be such that results coming after lastReturned are returned (where coming after means "greater than" if the filter is not reversed, "lesser than" otherwise; futher, whether the comparison is strict or not depends on inclusive).
        inclusive - whether or not we want to include the lastReturned in the newly returned page of results.
        Returns:
        a new filter that selects results coming after lastReturned.
      • isFullyCoveredBy

        boolean isFullyCoveredBy​(CachedPartition partition)
        Returns whether we can guarantee that a given cached partition contains all the data selected by this filter.
        Parameters:
        partition - the cached partition. This method assumed that the rows of this partition contains all the table columns.
        Returns:
        whether we can guarantee that all data selected by this filter are in partition.
      • isHeadFilter

        boolean isHeadFilter()
        Whether this filter selects the head of a partition (i.e. it isn't reversed and selects all rows up to a certain point).
        Returns:
        whether this filter selects the head of a partition.
      • selectsAllPartition

        boolean selectsAllPartition()
        Whether this filter selects all the row of a partition (it's an "identity" filter).
        Returns:
        whether this filter selects all the row of a partition (it's an "identity" filter).
      • selects

        boolean selects​(Clustering<?> clustering)
        Whether a given row is selected by this filter.
        Parameters:
        clustering - the clustering of the row to test the selection of.
        Returns:
        whether the row with clustering clustering is selected by this filter.
      • filterNotIndexed

        UnfilteredRowIterator filterNotIndexed​(ColumnFilter columnFilter,
                                               UnfilteredRowIterator iterator)
        Returns an iterator that only returns the rows of the provided iterator that this filter selects.

        This method is the "dumb" counterpart to getSlices(TableMetadata) in that it has no way to quickly get to what is actually selected, so it simply iterate over it all and filters out what shouldn't be returned. This should be avoided in general. Another difference with getSlices(TableMetadata) is that this method also filter the queried columns in the returned result, while the former assumes that the provided iterator has already done it.

        Parameters:
        columnFilter - the columns to include in the rows of the result iterator.
        iterator - the iterator for which we should filter rows.
        Returns:
        an iterator that only returns the rows (or rather Unfilted) from iterator that are selected by this filter.
      • getUnfilteredRowIterator

        UnfilteredRowIterator getUnfilteredRowIterator​(ColumnFilter columnFilter,
                                                       Partition partition)
        Given a partition, returns a row iterator for the rows of this partition that are selected by this filter.
        Parameters:
        columnFilter - the columns to include in the rows of the result iterator.
        partition - the partition containing the rows to filter.
        Returns:
        a unfiltered row iterator returning those rows (or rather Unfiltered) from partition that are selected by this filter.
      • shouldInclude

        boolean shouldInclude​(SSTableReader sstable)
        Whether the provided sstable may contain data that is selected by this filter (based on the sstable metadata).
        Parameters:
        sstable - the sstable for which we want to test the need for inclusion.
        Returns:
        whether sstable should be included to answer this filter.
      • toString

        java.lang.String toString​(TableMetadata metadata)
      • toCQLString

        java.lang.String toCQLString​(TableMetadata metadata)