Module datarush.library

Package com.pervasive.datarush.operators.select

package com.pervasive.datarush.operators.select
Provides operators for selecting a subset of the data set. Selection can be performed on various criteria:
  • whether a record meets some given requirement, expressed as a logical predicate. Logical predicates are defined as ScalarValuedFunctions which return a boolean result; a number of common predicates are predefined in Predicates.
  • whether a record falls within a given range of rows, based on position. Note that position is order-dependent; use on unordered data will yield non-deterministic results.
Random sampling of the data is also supported.

For operators which select a subset of fields from a record, refer to the operators in the record package.

  • Class
    Description
    FilterRows
    Filters records based on a specified predicate.
    LimitRows
    Truncates a flow to a fixed number of records.
    SampleMode
    The mode to use when applying random sampling.
    SampleRandomRows
    Apply random sampling to the input data.