Class InclusiveMetricsEvaluator

  • public class InclusiveMetricsEvaluator
    extends java.lang.Object
    Evaluates an Expression on a DataFile to test whether rows in the file may match.

    This evaluation is inclusive: it returns true if a file may match and false if it cannot match.

    Files are passed to eval(ContentFile), which returns true if the file may contain matching rows and false if the file cannot contain matching rows. Files may be skipped if and only if the return value of eval is false.

    Due to the comparison implementation of ORC stats, for float/double columns in ORC files, if the first value in a file is NaN, metrics of this file will report NaN for both upper and lower bound despite that the column could contain non-NaN data. Thus in some scenarios explicitly checks for NaN is necessary in order to not skip files that may contain matching data.

    • Constructor Detail

      • InclusiveMetricsEvaluator

        public InclusiveMetricsEvaluator​(Schema schema,
                                         Expression unbound)
      • InclusiveMetricsEvaluator

        public InclusiveMetricsEvaluator​(Schema schema,
                                         Expression unbound,
                                         boolean caseSensitive)
    • Method Detail

      • eval

        public boolean eval​(ContentFile<?> file)
        Test whether the file may contain records that match the expression.
        file - a data file
        false if the file cannot contain rows that match the expression, true otherwise.