Examples with TransformExpressionOperator com.linkedin.pinot.core.operator.transform.TransformExpressionOperator used on opensource projects

Example 6 with TransformExpressionOperator

use of com.linkedin.pinot.core.operator.transform.TransformExpressionOperator in project pinot by linkedin.

the class TransformExpressionOperatorTest method evaluateExpression.

/**
   * Helper method to evaluate one expression using the TransformOperator.
   * @param expression Expression to evaluate
   * @return Result of evaluation
   */
private double[] evaluateExpression(String expression) {
    Operator filterOperator = new MatchEntireSegmentOperator(_indexSegment.getSegmentMetadata().getTotalDocs());
    final BReusableFilteredDocIdSetOperator docIdSetOperator = new BReusableFilteredDocIdSetOperator(filterOperator, _indexSegment.getSegmentMetadata().getTotalDocs(), NUM_ROWS);
    final Map<String, BaseOperator> dataSourceMap = buildDataSourceMap(_indexSegment.getSegmentMetadata().getSchema());
    final MProjectionOperator projectionOperator = new MProjectionOperator(dataSourceMap, docIdSetOperator);
    Pql2Compiler compiler = new Pql2Compiler();
    List<TransformExpressionTree> expressionTrees = new ArrayList<>(1);
    expressionTrees.add(compiler.compileToExpressionTree(expression));
    TransformExpressionOperator transformOperator = new TransformExpressionOperator(projectionOperator, expressionTrees);
    transformOperator.open();
    TransformBlock transformBlock = (TransformBlock) transformOperator.getNextBlock();
    BlockValSet blockValueSet = transformBlock.getBlockValueSet(expression);
    double[] actual = blockValueSet.getDoubleValuesSV();
    transformOperator.close();
    return actual;
}