Examples with SMBJoinDesc org.apache.hadoop.hive.ql.plan.SMBJoinDesc used on opensource projects

Example 6 with SMBJoinDesc

use of org.apache.hadoop.hive.ql.plan.SMBJoinDesc in project hive by apache.

the class SparkSMBJoinHintOptimizer method removeSmallTableReduceSink.

/**
 * In bucket mapjoin, there are ReduceSinks that mark a small table parent (Reduce Sink are removed from big-table).
 * In SMB join these are not expected for any parents, either from small or big tables.
 * @param mapJoinOp
 */
@SuppressWarnings("unchecked")
private void removeSmallTableReduceSink(MapJoinOperator mapJoinOp) {
    SMBJoinDesc smbJoinDesc = new SMBJoinDesc(mapJoinOp.getConf());
    List<Operator<? extends OperatorDesc>> parentOperators = mapJoinOp.getParentOperators();
    for (int i = 0; i < parentOperators.size(); i++) {
        Operator<? extends OperatorDesc> par = parentOperators.get(i);
        if (i != smbJoinDesc.getPosBigTable()) {
            if (par instanceof ReduceSinkOperator) {
                List<Operator<? extends OperatorDesc>> grandParents = par.getParentOperators();
                Preconditions.checkArgument(grandParents.size() == 1, "AssertionError: expect # of parents to be 1, but was " + grandParents.size());
                Operator<? extends OperatorDesc> grandParent = grandParents.get(0);
                grandParent.removeChild(par);
                grandParent.setChildOperators(Utilities.makeList(mapJoinOp));
                mapJoinOp.getParentOperators().set(i, grandParent);
            }
        }
    }
}