Examples with IdentityExpression org.apache.hadoop.hive.ql.exec.vector.expressions.IdentityExpression used on opensource projects

Example 1 with IdentityExpression

use of org.apache.hadoop.hive.ql.exec.vector.expressions.IdentityExpression in project hive by apache.

the class Vectorizer method vectorizeSelectOperator.

public static Operator<? extends OperatorDesc> vectorizeSelectOperator(Operator<? extends OperatorDesc> selectOp, VectorizationContext vContext) throws HiveException {
    SelectDesc selectDesc = (SelectDesc) selectOp.getConf();
    VectorSelectDesc vectorSelectDesc = new VectorSelectDesc();
    selectDesc.setVectorDesc(vectorSelectDesc);
    List<ExprNodeDesc> colList = selectDesc.getColList();
    int index = 0;
    final int size = colList.size();
    VectorExpression[] vectorSelectExprs = new VectorExpression[size];
    int[] projectedOutputColumns = new int[size];
    for (int i = 0; i < size; i++) {
        ExprNodeDesc expr = colList.get(i);
        VectorExpression ve = vContext.getVectorExpression(expr);
        projectedOutputColumns[i] = ve.getOutputColumn();
        if (ve instanceof IdentityExpression) {
            // Suppress useless evaluation.
            continue;
        }
        vectorSelectExprs[index++] = ve;
    }
    if (index < size) {
        vectorSelectExprs = Arrays.copyOf(vectorSelectExprs, index);
    }
    vectorSelectDesc.setSelectExpressions(vectorSelectExprs);
    vectorSelectDesc.setProjectedOutputColumns(projectedOutputColumns);
    return OperatorFactory.getVectorOperator(selectOp.getCompilationOpContext(), selectDesc, vContext);
}