use of org.apache.hadoop.hive.ql.optimizer.unionproc.UnionProcContext.UnionParseContext in project hive by apache.
the class GenMRUnion1 method processMapOnlyUnion.
/**
* Process the union if all sub-queries are map-only
*
* @return
* @throws SemanticException
*/
private Object processMapOnlyUnion(UnionOperator union, Stack<Node> stack, GenMRProcContext ctx, UnionProcContext uCtx) throws SemanticException {
// merge currTask from multiple topOps
GenMRUnionCtx uCtxTask = ctx.getUnionTask(union);
if (uCtxTask != null) {
// get task associated with this union
Task<? extends Serializable> uTask = ctx.getUnionTask(union).getUTask();
if (uTask != null) {
if (ctx.getCurrTask() != null && ctx.getCurrTask() != uTask) {
// if ctx.getCurrTask() is in rootTasks, should be removed
ctx.getRootTasks().remove(ctx.getCurrTask());
}
ctx.setCurrTask(uTask);
}
}
UnionParseContext uPrsCtx = uCtx.getUnionParseContext(union);
ctx.getMapCurrCtx().put(union, new GenMapRedCtx(ctx.getCurrTask(), ctx.getCurrAliasId()));
// if the union is the first time seen, set current task to GenMRUnionCtx
uCtxTask = ctx.getUnionTask(union);
if (uCtxTask == null) {
uCtxTask = new GenMRUnionCtx(ctx.getCurrTask());
ctx.setUnionTask(union, uCtxTask);
}
Task<? extends Serializable> uTask = ctx.getCurrTask();
if (uTask.getParentTasks() == null || uTask.getParentTasks().isEmpty()) {
if (!ctx.getRootTasks().contains(uTask)) {
ctx.getRootTasks().add(uTask);
}
}
return true;
}
use of org.apache.hadoop.hive.ql.optimizer.unionproc.UnionProcContext.UnionParseContext in project hive by apache.
the class GenMRUnion1 method process.
/**
* Union Operator encountered . Currently, the algorithm is pretty simple: If
* all the sub-queries are map-only, don't do anything. Otherwise, insert a
* FileSink on top of all the sub-queries.
*
* This can be optimized later on.
*
* @param nd
* the file sink operator encountered
* @param opProcCtx
* context
*/
@Override
public Object process(Node nd, Stack<Node> stack, NodeProcessorCtx opProcCtx, Object... nodeOutputs) throws SemanticException {
UnionOperator union = (UnionOperator) nd;
GenMRProcContext ctx = (GenMRProcContext) opProcCtx;
ParseContext parseCtx = ctx.getParseCtx();
UnionProcContext uCtx = parseCtx.getUCtx();
// Map-only subqueries can be optimized in future to not write to a file in
// future
Map<Operator<? extends OperatorDesc>, GenMapRedCtx> mapCurrCtx = ctx.getMapCurrCtx();
if (union.getConf().isAllInputsInSameReducer()) {
// All inputs of this UnionOperator are in the same Reducer.
// We do not need to break the operator tree.
mapCurrCtx.put((Operator<? extends OperatorDesc>) nd, new GenMapRedCtx(ctx.getCurrTask(), ctx.getCurrAliasId()));
return null;
}
UnionParseContext uPrsCtx = uCtx.getUnionParseContext(union);
ctx.setCurrUnionOp(union);
// map-reduce job
if (uPrsCtx.allMapOnlySubQ()) {
return processMapOnlyUnion(union, stack, ctx, uCtx);
}
assert uPrsCtx != null;
Task<? extends Serializable> currTask = ctx.getCurrTask();
int pos = UnionProcFactory.getPositionParent(union, stack);
Task<? extends Serializable> uTask = null;
MapredWork uPlan = null;
// union is encountered for the first time
GenMRUnionCtx uCtxTask = ctx.getUnionTask(union);
if (uCtxTask == null) {
uPlan = GenMapRedUtils.getMapRedWork(parseCtx);
uTask = TaskFactory.get(uPlan, parseCtx.getConf());
uCtxTask = new GenMRUnionCtx(uTask);
ctx.setUnionTask(union, uCtxTask);
} else {
uTask = uCtxTask.getUTask();
}
// Copy into the current union task plan if
if (uPrsCtx.getMapOnlySubq(pos) && uPrsCtx.getRootTask(pos)) {
processSubQueryUnionMerge(ctx, uCtxTask, union, stack);
if (ctx.getRootTasks().contains(currTask)) {
ctx.getRootTasks().remove(currTask);
}
} else // If it a map-reduce job, create a temporary file
{
// is the current task a root task
if (shouldBeRootTask(currTask) && !ctx.getRootTasks().contains(currTask) && (currTask.getParentTasks() == null || currTask.getParentTasks().isEmpty())) {
ctx.getRootTasks().add(currTask);
}
processSubQueryUnionCreateIntermediate(union.getParentOperators().get(pos), union, uTask, ctx, uCtxTask);
// the currAliasId and CurrTopOp is not valid any more
ctx.setCurrAliasId(null);
ctx.setCurrTopOp(null);
ctx.getOpTaskMap().put(null, uTask);
}
ctx.setCurrTask(uTask);
mapCurrCtx.put((Operator<? extends OperatorDesc>) nd, new GenMapRedCtx(ctx.getCurrTask(), null));
return true;
}
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