// ExSampleTcb constructor
//
// 1. Allocate buffer pool.
// 2. Allocate parent queues and initialize private state.
// 3. Fixup expressions.
//
ExSampleTcb::ExSampleTcb
(const ExSampleTdb & myTdb,
const ex_tcb & child_tcb,
ex_globals * glob
) :
ex_tcb(myTdb, 1, glob)
{
Space * space = (glob ? glob->getSpace() : 0);
CollHeap * heap = (glob ? glob->getDefaultHeap() : 0);
childTcb_ = &child_tcb;
// get the queue that child use to communicate with me
qchild_ = child_tcb.getParentQueue();
// Allocate the queue to communicate with parent
qparent_.down = new(space) ex_queue(ex_queue::DOWN_QUEUE,
myTdb.queueSizeDown_,
myTdb.criDescDown_,
space);
// Allocate the private state in each entry of the down queue
ExSamplePrivateState *p
= new(space) ExSamplePrivateState(this);
qparent_.down->allocatePstate(p, this);
delete p;
qparent_.up = new(space) ex_queue(ex_queue::UP_QUEUE,
myTdb.queueSizeUp_,
myTdb.criDescUp_,
space);
// Intialized processedInputs_ to the next request to process
processedInputs_ = qparent_.down->getTailIndex();
// Fixup the sample expression
//
if (initExpr())
initExpr()->fixup(0, getExpressionMode(), this, space, heap, FALSE, glob);
if (balanceExpr())
balanceExpr()->fixup(0, getExpressionMode(), this, space, heap, FALSE, glob);
if (postPred())
postPred()->fixup(0, getExpressionMode(), this, space, heap, FALSE, glob);
}
// work - doit...
//
//
short ExSequenceTcb::work()
{
// If there are no parent requests on the queue, then there cannot
// be anything to do here.
//
if (qparent_.down->isEmpty())
return WORK_OK;
ex_queue_entry * pentry_down;
ExSequencePrivateState * pstate;
ex_queue::down_request request;
// Take any new parent requests and pass them on to the child as long
// as the child's queue is not full. processedInputs_ maintains the
// Queue index of the last request that was passed on.
//
for(queue_index tail = qparent_.down->getTailIndex();
(processedInputs_ != tail) && (!qchild_.down->isFull());
processedInputs_++ )
{
pentry_down = qparent_.down->getQueueEntry(processedInputs_);
pstate = (ExSequencePrivateState*) pentry_down->pstate;
request = pentry_down->downState.request;
// If the request has already been cancelled don't pass it to the
// child. Instead, just mark the request as done. This will trigger
// a EOD reply when this request gets worked on.
//
if (request == ex_queue::GET_NOMORE)
{
// LCOV_EXCL_START
pstate->step_ = ExSeq_DONE;
// LCOV_EXCL_STOP
}
else
{
pstate->step_ = ExSeq_WORKING_READ;
// Pass the request to the child
//
ex_queue_entry * centry = qchild_.down->getTailEntry();
centry->downState.request = ex_queue::GET_ALL;
centry->downState.requestValue = 11;
centry->downState.parentIndex = processedInputs_;
centry->passAtp(pentry_down);
qchild_.down->insert();
}
} // end for processedInputs_
pentry_down = qparent_.down->getHeadEntry();
pstate = (ExSequencePrivateState*) pentry_down->pstate;
request = pentry_down->downState.request;
// Take any child replies and process them. Return the processed
// rows as long the parent queue has room.
//
while (1)
{
// If we have satisfied the parent request (or it was cancelled),
// then stop processing rows, cancel any outstanding child
// requests, and set this request to the CANCELLED state.
//
if ((pstate->step_ == ExSeq_WORKING_READ) ||
(pstate->step_ == ExSeq_WORKING_RETURN))
{
if ((request == ex_queue::GET_NOMORE) ||
((request == ex_queue::GET_N) &&
(pentry_down->downState.requestValue
<= (Lng32)pstate->matchCount_)))
{
qchild_.down->cancelRequestWithParentIndex
(qparent_.down->getHeadIndex());
pstate->step_ = ExSeq_CANCELLED;
}
}
switch (pstate->step_)
{
// ExSeq_CANCELLED
//
// Transition to this state from ...
// 1. ExSeq_Error - After the error has been processed.
// 2. ExSeq_Working - If enough rows have been returned.
// 3. ExSeq_Working - If the request was cancelled.
//
// Remain in this state until ..
// 1. All rows from the child including EOD are consumed
//
// Transition from this state to ...
// 1. ExSeq_DONE - In all cases.
//
case ExSeq_CANCELLED:
{
// There are no extra rows to process from the child yet,
// so try again later.
//
if (qchild_.up->isEmpty())
{
return WORK_OK;
}
ex_queue_entry * centry = qchild_.up->getHeadEntry();
ex_queue::up_status child_status = centry->upState.status;
// If this is the EOD, transition to the ExSeq_DONE state.
//
if (child_status == ex_queue::Q_NO_DATA)
pstate->step_ = ExSeq_DONE;
// Discard the child row.
qchild_.up->removeHead();
break;
}
// ExSeq_ERROR
//
// Transition to this state from ...
// 1. ExSeq_WORKING_READ - a child reply with the type SQLERROR.
// 2. ExSeq_WORKING_RETURN
// 3. ExSeq_OVERFLOW_READ
// 4. ExSeq_OVERFLOW_WRITE
// Remain in this state until ..
// 1. The error row has been returned to the parent.
//
// Transition from this state to ...
// 1. ExSeq_CANCELLED - In all cases.
//
case ExSeq_ERROR:
{
// If there is no room in the parent queue for the reply,
// try again later.
//
if (qparent_.up->isFull())
// LCOV_EXCL_START
return WORK_OK;
// LCOV_EXCL_STOP
ex_queue_entry *pentry_up = qparent_.up->getTailEntry();
// Cancel the child request - there must be a child request in
// progress to get to the ExSeq_ERROR state.
//
qchild_.down->cancelRequestWithParentIndex
(qparent_.down->getHeadIndex());
// Construct and return the error row.
//
if (workAtp_->getDiagsArea()) {
ComDiagsArea * da = workAtp_->getDiagsArea();
pentry_up->setDiagsArea(da);
da->incrRefCount();
workAtp_->setDiagsArea(0);
}
pentry_up->upState.status = ex_queue::Q_SQLERROR;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex = qparent_.down->getHeadIndex();
pentry_up->upState.setMatchNo(pstate->matchCount_);
qparent_.up->insert();
// Transition to the ExSeq_CANCELLED state.
//
pstate->step_ = ExSeq_CANCELLED;
break;
}
// ExSeq_WORKING_READ
//
// Transition to this state from ...
// 1. ExSeq_EMPTY - If a request is started.
// 2. ExSeq_WORKING_RETURN -
// 3. ExSeq_OVERFLOW_WRITE -
// Remain in this state until ...
// 1. All child replies including EOD have been processed.
// 2. A SQLERROR row is received.
// 3. Enough rows have been returned.
// 4. The request is cancelled.
// 5. End of partition is reached
// Transition from this state to ...
// 2. ExSeq_ERROR - If an SQLERROR rows is received.
// 3. ExSeq_CANCELLED - If the request is cancelled.
// 4. ExSeq_WORKING_RETURN
// 5. ExSeq_OVERFLOW_WRITE -
case ExSeq_WORKING_READ:
{
if(!isUnboundedFollowing() && isHistoryFull()) {
pstate->step_ = ExSeq_WORKING_RETURN;
break;
}
// If there are no replies, try again later.
//
if (qchild_.up->isEmpty())
return WORK_OK;
ex_queue_entry * centry = qchild_.up->getHeadEntry();
switch (centry->upState.status)
{
// A data row from the child.
//
case ex_queue::Q_OK_MMORE:
{
tupp_descriptor histTupp;
workAtp_->copyAtp(pentry_down->getAtp());
workAtp_->getTupp(myTdb().tuppIndex_) = &histTupp;
if ( checkPartitionChangeExpr() &&
currentHistRowPtr_)
{
workAtp_->getTupp
(myTdb().tuppIndex_).setDataPointer(currentHistRowPtr_);
// Check whether the partition changed
ex_expr::exp_return_type retCode = checkPartitionChangeExpr()->eval(workAtp_, centry->getAtp());
if (retCode == ex_expr::EXPR_ERROR)
{
// LCOV_EXCL_START
updateDiagsArea(centry);
pstate->step_ = ExSeq_ERROR;
break;
// LCOV_EXCL_STOP
}
if ( retCode == ex_expr::EXPR_FALSE)
{
setPartitionEnd(TRUE);
pstate->step_ = ExSeq_END_OF_PARTITION;
break;
}
}
if (isUnboundedFollowing() )
{
if (OLAPBuffersFlushed_)
{
OLAPBuffersFlushed_ = FALSE;// current row is the first one in first buffer already
}
else
{
NABoolean noMemory =
advanceHistoryRow( TRUE /* checkMemoryPressure */);
if (noMemory)
{
pstate->step_ = ExSeq_OVERFLOW_WRITE;
cluster_->nextBufferToFlush_ = firstOLAPBuffer_;
cluster_->afterLastBufferToFlush_ = NULL;//flush them all
// If it is the first overflow, for this partition
if ( ! memoryPressureDetected_ ) {
memoryPressureDetected_ = TRUE;
} // memory pressure detected
break;
}
}
}
else
{
advanceHistoryRow();
}
workAtp_->getTupp
(myTdb().tuppIndex_).setDataPointer(currentHistRowPtr_);
ex_expr::exp_return_type retCode = ex_expr::EXPR_OK;
// Apply the read phase sequence function expression to compute
// the values of the sequence functions.
if (sequenceExpr())
{
retCode = sequenceExpr()->eval(workAtp_, centry->getAtp());
if (retCode == ex_expr::EXPR_ERROR)
{
updateDiagsArea(centry);
pstate->step_ = ExSeq_ERROR;
break;
}
}
// merge the child's diags area into the work atp
updateDiagsArea(centry);
qchild_.up->removeHead();
break;
}
// The EOD from the child. Transition to ExSeq_DONE.
//
case ex_queue::Q_NO_DATA:
{
setPartitionEnd(TRUE);
if (isHistoryEmpty())
{
pstate->step_ = ExSeq_DONE;
qchild_.up->removeHead();
}
else
{
pstate->step_ = ExSeq_END_OF_PARTITION;
}
}
break;
// An SQLERROR from the child. Transition to ExSeq_ERROR.
//
case ex_queue::Q_SQLERROR:
updateDiagsArea(centry);
pstate->step_ = ExSeq_ERROR;
break;
}
}
break;
// ExSeq_WORKING_RETURN
//
// Transition to this state from ...
// 1. ExSeq_WORKING_READ -
// 2. ExSeq_OVERFLOW_READ -
// 3. ExSeq_END_OF_PARTITION -
// Remain in this state until ...
// 1. All rows are returned.
// 2. A SQLERROR row is received.
// 3. Enough rows have been returned.
//
// Transition from this state to ...
// 1. ExSeq_DONE - If all the child rows including EOD have
// been processed.
// 2. ExSeq_ERROR - If an SQLERROR rows is received.
// 3. ExSeq_CANCELLED - If enough rows have been returned.
// 4. ExSeq_CANCELLED - If the request is cancelled.
// 5. ExSeq_WORKING_RETURN
// 6. ExSeq_DONE
// 7. ExSeq_OVERFLOW_READ
case ExSeq_WORKING_RETURN:
{
// If there is not room in the parent Queue for the reply,
// try again later.
//
if (qparent_.up->isFull())
return WORK_OK;
if(isHistoryEmpty())
{
ex_queue_entry * centry = NULL;
if(!qchild_.up->isEmpty())
{
centry = qchild_.up->getHeadEntry();
}
if(centry && (centry->upState.status == ex_queue::Q_NO_DATA))
{
pstate->step_ = ExSeq_DONE;
qchild_.up->removeHead();
}
else
{
pstate->step_ = ExSeq_WORKING_READ;
if (getPartitionEnd())
{
initializeHistory();
}
}
break;
}
if(!canReturnRows() &&
!getPartitionEnd() &&
!isUnboundedFollowing() &&
!isOverflowStarted()) // redundant? because not unbounded ...
{
pstate->step_ = ExSeq_WORKING_READ;
break;
}
ex_queue_entry * pentry_up = qparent_.up->getTailEntry();
pentry_up->copyAtp(pentry_down);
// Try to allocate a tupp.
//
if (pool_->get_free_tuple(pentry_up->getTupp(myTdb().tuppIndex_),
recLen()))
// LCOV_EXCL_START
return WORK_POOL_BLOCKED;
// LCOV_EXCL_STOP
char *tuppData = pentry_up->getTupp
(myTdb().tuppIndex_).getDataPointer();
advanceReturnHistoryRow();
char *histData = currentRetHistRowPtr_;
pentry_up->getTupp
(myTdb().tuppIndex_).setDataPointer(histData);
ex_expr::exp_return_type retCode = ex_expr::EXPR_OK;
// Apply the return phase expression
if(returnExpr())
{
retCode = returnExpr()->eval(pentry_up->getAtp(),workAtp_);
if (retCode == ex_expr::EXPR_ERROR)
{
// LCOV_EXCL_START
pstate->step_ = ExSeq_ERROR;
break;
// LCOV_EXCL_STOP
}
}
retCode = ex_expr::EXPR_OK;
//Apply post predicate expression
if (postPred())
{
retCode = postPred()->eval(pentry_up->getAtp(),pentry_up->getAtp());
if (retCode == ex_expr::EXPR_ERROR)
{
// LCOV_EXCL_START
pstate->step_ = ExSeq_ERROR;
break;
// LCOV_EXCL_STOP
}
}
//pentry_up->getAtp()->display("return eval result", myTdb().getCriDescUp());
//
// Case-10-030724-7963: we are done pointing the tupp at the
// history buffer, so point it back to the SQL buffer.
//
pentry_up->getTupp
(myTdb().tuppIndex_).setDataPointer(tuppData);
switch(retCode) {
case ex_expr::EXPR_OK:
case ex_expr::EXPR_TRUE:
case ex_expr::EXPR_NULL:
// Copy the row that was computed in the history buffer,
// to the space previously allocated in the SQL buffer.
str_cpy_all(tuppData, histData, recLen());
// Return the processed row.
//
// Finalize the queue entry, then insert it
//
pentry_up->upState.status = ex_queue::Q_OK_MMORE;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex =
qparent_.down->getHeadIndex();
pstate->matchCount_++;
pentry_up->upState.setMatchNo(pstate->matchCount_);
qparent_.up->insert();
break;
// If the selection predicate returns FALSE,
// do not return the child row.
//
case ex_expr::EXPR_FALSE:
break;
// If the selection predicate returns an ERROR,
// go to the error processing state.
//
case ex_expr::EXPR_ERROR:
// LCOV_EXCL_START
pstate->step_ = ExSeq_ERROR;
// LCOV_EXCL_STOP
break;
}
// MV --
// Now, if there are no errors so far, evaluate the
// cancel expression
if ((pstate->step_ != ExSeq_ERROR) && cancelExpr())
{
// Temporarily point the tupp to the tail of the
// history buffer for evaluating the
// expressions.
//
pentry_up->getTupp
(myTdb().tuppIndex_).setDataPointer(histData);
retCode =
cancelExpr()->eval(pentry_up->getAtp(),pentry_up->getAtp());
// We are done pointing the tupp at the history
// buffer, so point it back to the SQL buffer.
//
pentry_up->getTupp
(myTdb().tuppIndex_).setDataPointer(tuppData);
if (retCode == ex_expr::EXPR_TRUE)
{
qchild_.down->cancelRequestWithParentIndex
(qparent_.down->getHeadIndex());
pstate->step_ = ExSeq_CANCELLED;
}
}
updateHistRowsToReturn();
if ( isOverflowStarted() )
{
numberOfRowsReturnedBeforeReadOF_ ++;
if (numberOfRowsReturnedBeforeReadOF_ == maxNumberOfRowsReturnedBeforeReadOF_)
{
firstOLAPBufferFromOF_ = currentRetOLAPBuffer_->getNext();
if (firstOLAPBufferFromOF_ == NULL)
{
firstOLAPBufferFromOF_ = firstOLAPBuffer_;
}
for( Int32 i = 0; i < numberOfWinOLAPBuffers_; i++)
{
firstOLAPBufferFromOF_ = firstOLAPBufferFromOF_->getNext();
if (firstOLAPBufferFromOF_ == NULL)
{
firstOLAPBufferFromOF_ = firstOLAPBuffer_;
}
}
numberOfOLAPBuffersFromOF_ = numberOfOLAPBuffers_ - numberOfWinOLAPBuffers_;
cluster_->nextBufferToRead_ = firstOLAPBufferFromOF_;
HashBuffer * afterLast = firstOLAPBufferFromOF_;
// last buffer to read into is the current buffer - maybe ?
for ( Lng32 bufcount = numberOfOLAPBuffersFromOF_ ;
bufcount ;
bufcount-- ) {
afterLast = afterLast->getNext() ;
// Don't cycle back if bufcount == 1 because the logic in
// Cluster::read relies on the NULL ptr to stop reading
if ( bufcount > 1 && ! afterLast )
afterLast = firstOLAPBuffer_; // cycle back
}
// The last buffer to read to is always the current buffer
// ex_assert ( afterLast == currentRetOLAPBuffer_->getNext(),
// "Miscalculated the last buffer to read into");
cluster_->afterLastBufferToRead_ = afterLast;
pstate->step_ = ExSeq_OVERFLOW_READ;
}
}
}
break;
// ExSeq_END_OF_PARTITION
//
// Transition to this state from ...
// 1. ExSeq_WORKING_READ -
// Transition from this state to ...
// 1. ExSeq_OVERFLOW_WRITE
// 2. ExSeq_WORKING_RETURN
case ExSeq_END_OF_PARTITION:
{
setPartitionEnd(TRUE);
if (lastRow_ && isUnboundedFollowing())
{
ex_assert(currentHistRowPtr_ != NULL, "ExSequenceTcb::work() - currentHistRowPtr_ is a NULL pointer");
str_cpy_all(lastRow_, currentHistRowPtr_, recLen());
}
if ( isOverflowStarted() ) // we are overflowing
{
cluster_->nextBufferToFlush_ = firstOLAPBuffer_;
// do not flush beyond the current buffer
cluster_->afterLastBufferToFlush_ = currentOLAPBuffer_->getNext();
pstate->step_ = ExSeq_OVERFLOW_WRITE;
}
else
{
pstate->step_ = ExSeq_WORKING_RETURN;
}
}
break;
// ExSeq_OVERFLOW_WRITE
//
// Transition to this state from ...
// 1. ExSeq_WORKING_READ -
// 2. ExSeq_END_OF_PARTITION -
// Remain in this state until ...
// 1. OLAPbuffers are written to oveflow space.
// 2. An error occurs
//
// Transition from this state to ...
// 1. ExSeq_OVERFLOW_READ
// 2. ExSeq_ERROR - If an error occurs
case ExSeq_OVERFLOW_WRITE:
{
if (!overflowEnabled_)
{
// LCOV_EXCL_START
// used for debugging when CmpCommon::getDefault(EXE_BMO_DISABLE_OVERFLOW)is set to off ;
updateDiagsArea(EXE_OLAP_OVERFLOW_NOT_SUPPORTED);
pstate->step_ = ExSeq_ERROR;
break;
// LCOV_EXCL_STOP
}
ex_assert(isUnboundedFollowing(),"");
if ( ! cluster_->flush(&rc_) ) { // flush the buffers
// LCOV_EXCL_START
// if no errors this code path is not visited
if ( rc_ )
{ // some error
updateDiagsArea( rc_);
pstate->step_ = ExSeq_ERROR;
break;
}
// LCOV_EXCL_STOP
// not all the buffers are completely flushed. An I/O is pending
// LCOV_EXCL_START
// maybe we cane remove in the future
return WORK_OK;
// LCOV_EXCL_STOP
}
// At this point -- all the buffers were completely flushed
OLAPBuffersFlushed_ = TRUE;
if (getPartitionEnd())
{
firstOLAPBufferFromOF_ = firstOLAPBuffer_;
numberOfOLAPBuffersFromOF_ = numberOfOLAPBuffers_;
cluster_->nextBufferToRead_ = firstOLAPBufferFromOF_;
// First time we read and fill all the buffers
cluster_->afterLastBufferToRead_ = NULL;
pstate->step_ = ExSeq_OVERFLOW_READ;
}
else
{
pstate->step_ = ExSeq_WORKING_READ;
}
}
break;
// ExSeq_OVERFLOW_READ
//
// Transition to this state from ...
// 1. ExSeq_OVERFLOW_WRITE
// 2. ExSeq_WORKING_RETURN
// Remain in this state until ...
// 1. OLAPbuffers are read from oveflow space.
// 2. An error occurs
//
// Transition from this state to ...
// 1. ExSeq_WORKING_RETURN
// 2. ExSeq_ERROR - If an error occurs
case ExSeq_OVERFLOW_READ:
{
assert(firstOLAPBufferFromOF_ &&
isUnboundedFollowing() );
if ( ! cluster_->read(&rc_) ) {
// LCOV_EXCL_START
if ( rc_ ) { // some error
updateDiagsArea( rc_);
pstate->step_ = ExSeq_ERROR;
break;
}
// LCOV_EXCL_STOP
// not all the buffers are completely read. An I/O is pending
// LCOV_EXCL_START
return WORK_OK;
// LCOV_EXCL_STOP
}
numberOfRowsReturnedBeforeReadOF_ = 0;
pstate->step_ = ExSeq_WORKING_RETURN;
}
break;
// ExSeq_DONE
//
// Transition to the state from ...
// 1. ExSeq_WORKING_RETURN - if all child rows have been processed.
// 2. ExSeq_CANCELLED - if all child rows have been consumed.
// 3. ExSeq_EMPTY - if the request was DOA.
//
// Remain in this state until ...
// 1. The EOD is returned to the parent.
//
// Transition from this state to ...
// 1. ExSeq_EMPTY - In all cases.
//
case ExSeq_DONE:
{
// If there is not any room in the parent's queue,
// try again later.
//
if (qparent_.up->isFull())
// LCOV_EXCL_START
return WORK_OK;
// LCOV_EXCL_STOP
ex_queue_entry * pentry_up = qparent_.up->getTailEntry();
pentry_up->upState.status = ex_queue::Q_NO_DATA;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex = qparent_.down->getHeadIndex();
pentry_up->upState.setMatchNo(pstate->matchCount_);
qparent_.down->removeHead();
qparent_.up->insert();
// Re-initialize pstate
//
pstate->step_ = ExSeq_EMPTY;
pstate->matchCount_ = 0;
workAtp_->release();
// Initialize the history buffer in preparation for the
// next request.
//
initializeHistory();
// If there are no more requests, simply return.
//
if (qparent_.down->isEmpty())
return WORK_OK;
// LCOV_EXCL_START
// If we haven't given to our child the new head
// index return and ask to be called again.
//
if (qparent_.down->getHeadIndex() == processedInputs_)
return WORK_CALL_AGAIN;
// Position at the new head of the request queue.
//
pentry_down = qparent_.down->getHeadEntry();
pstate = (ExSequencePrivateState*) pentry_down->pstate;
request = pentry_down->downState.request;
// LCOV_EXCL_STOP
}
break;
} // switch pstate->step_
} // while
}
// ExSequenceTcb constructor
//
// 1. Allocate buffer pool.
// 2. Allocate parent queues and initialize private state.
// 3. Fixup expressions.
//
ExSequenceTcb::ExSequenceTcb (const ExSequenceTdb & myTdb,
const ex_tcb & child_tcb,
ex_globals * glob) :
ex_tcb(myTdb, 1, glob),
lastRow_(NULL),
clusterDb_(NULL),
cluster_(NULL),
ioEventHandler_(NULL),
OLAPBuffersFlushed_(FALSE),
firstOLAPBuffer_(NULL),
lastOLAPBuffer_(NULL),
rc_(EXE_OK),
olapBufferSize_(0),
maxNumberOfOLAPBuffers_(0),
numberOfOLAPBuffers_(0),
minNumberOfOLAPBuffers_(0),
memoryPressureDetected_(FALSE)
{
Space * space = (glob ? glob->getSpace() : 0);
CollHeap * heap = (glob ? glob->getDefaultHeap() : 0);
heap_ = heap;
childTcb_ = &child_tcb;
// Allocate the buffer pool
#pragma nowarn(1506) // warning elimination
pool_ = new(space) sql_buffer_pool(myTdb.numBuffers_,
myTdb.bufferSize_,
space);
allocRowLength_ = ROUND8(myTdb.recLen_);
#pragma warn(1506) // warning elimination
// Initialize the machinery for maintaining the row history for
// computing sequence functions.
//
maxNumberHistoryRows_ = myTdb.maxHistoryRows_;
minFollowing_ = myTdb.minFollowing_;
unboundedFollowing_ = myTdb.isUnboundedFollowing();
maxNumberOfOLAPBuffers_ = myTdb.maxNumberOfOLAPBuffers_;//testing
olapBufferSize_ = myTdb.OLAPBufferSize_ ;
maxRowsInOLAPBuffer_ = myTdb.maxRowsInOLAPBuffer_;
minNumberOfOLAPBuffers_ = myTdb.minNumberOfOLAPBuffers_;
numberOfWinOLAPBuffers_ = myTdb.numberOfWinOLAPBuffers_;
overflowEnabled_ = ! myTdb.isNoOverflow();
ex_assert( maxNumberOfOLAPBuffers_ >= minNumberOfOLAPBuffers_ ,
"maxNumberOfOLAPBuffers is too small");
// Initialize history parameters
// For unbounded following -- also create/initialize clusterDb, cluster
initializeHistory();
// get the queue that child use to communicate with me
qchild_ = child_tcb.getParentQueue();
// Allocate the queue to communicate with parent
qparent_.down = new(space) ex_queue(ex_queue::DOWN_QUEUE,
myTdb.initialQueueSizeDown_,
myTdb.criDescDown_,
space);
// Allocate the private state in each entry of the down queue
ExSequencePrivateState *p
= new(space) ExSequencePrivateState(this);
qparent_.down->allocatePstate(p, this);
delete p;
qparent_.up = new(space) ex_queue(ex_queue::UP_QUEUE,
myTdb.initialQueueSizeUp_,
myTdb.criDescUp_,
space);
// Intialized processedInputs_ to the next request to process
processedInputs_ = qparent_.down->getTailIndex();
workAtp_ = allocateAtp(myTdb.criDescUp_, space);
// Fixup the sequence function expression. This requires the standard
// expression fixup plus initializing the GetRow method for the sequence
// clauses.
//
if (sequenceExpr())
{
((ExpSequenceExpression*)sequenceExpr())->seqFixup
((void*)this, GetHistoryRow, GetHistoryRowOLAP);
sequenceExpr()->fixup(0, getExpressionMode(), this, space, heap_, FALSE, glob);
}
if (returnExpr())
{
((ExpSequenceExpression*)returnExpr())->seqFixup
((void*)this, GetHistoryRow, GetHistoryRowFollowingOLAP);
returnExpr()->fixup(0, getExpressionMode(), this, space, heap_, FALSE, glob);
}
if (postPred())
postPred()->fixup(0, getExpressionMode(), this, space, heap_, FALSE, glob);
if (cancelExpr())
cancelExpr()->fixup(0, getExpressionMode(), this, space, heap_, FALSE, glob);
if (checkPartitionChangeExpr())
{
((ExpSequenceExpression*)checkPartitionChangeExpr())->seqFixup
((void*)this, GetHistoryRow, GetHistoryRowOLAP);
checkPartitionChangeExpr()->fixup(0, getExpressionMode(), this, space, heap_, FALSE, glob);
}
}
// work - doit...
//
//
short ExSampleTcb::work()
{
// If there are no parent requests on the queue, then there cannot
// be anything to do here.
//
if (qparent_.down->isEmpty())
return WORK_OK;
ex_queue_entry * pentry_down;
ExSamplePrivateState * pstate;
ex_queue::down_request request;
// Take any new parent requests and pass them on to the child as long
// as the child's queue is not full. processedInputs_ maintains the
// Queue index of the last request that was passed on.
//
for(queue_index tail = qparent_.down->getTailIndex();
(processedInputs_ != tail) && (!qchild_.down->isFull());
processedInputs_++ )
{
pentry_down = qparent_.down->getQueueEntry(processedInputs_);
pstate = (ExSamplePrivateState*) pentry_down->pstate;
request = pentry_down->downState.request;
// If the request has already been cancelled don't pass it to the
// child. Instead, just mark the request as done. This will trigger
// a EOD reply when this request gets worked on.
//
if (request == ex_queue::GET_NOMORE)
{
pstate->step_ = ExSamp_DONE;
}
else
{
pstate->step_ = ExSamp_PREWORK;
// Pass the request to the child
//
ex_queue_entry * centry = qchild_.down->getTailEntry();
centry->downState.request = ex_queue::GET_ALL;
centry->downState.requestValue = 11;
centry->downState.parentIndex = processedInputs_;
centry->passAtp(pentry_down);
qchild_.down->insert();
// Copy the input atp to the work atp for this request
//
pstate->workAtp_->copyAtp(pentry_down->getAtp());
}
} // end for processedInputs_
pentry_down = qparent_.down->getHeadEntry();
pstate = (ExSamplePrivateState*) pentry_down->pstate;
request = pentry_down->downState.request;
// If the request has not been worked on yet, then
// initialize the presistent expression variable data and
// switch to the WORKING state.
//
if(pstate->step_ == ExSamp_PREWORK)
{
pstate->step_ = ExSamp_WORKING;
if(balanceExpr()) balanceExpr()->initializePersistentData();
}
ExOperStats *statsEntry = getStatsEntry();
// Take any child replies and process them. Return the processed
// rows as long the parent queue has room.
//
while (1)
{
// If we have satisfied the parent request (or it was cancelled),
// then stop processing rows, cancel any outstanding child
// requests, and set this request to the CANCELLED state.
//
if((pstate->step_ == ExSamp_WORKING) ||
(pstate->step_ == ExSamp_RETURNINGROWS))
{
if ((request == ex_queue::GET_NOMORE) ||
((request == ex_queue::GET_N) &&
(pentry_down->downState.requestValue
<= (Lng32)pstate->matchCount_)))
{
qchild_.down->cancelRequestWithParentIndex
(qparent_.down->getHeadIndex());
pstate->step_ = ExSamp_CANCELLED;
}
}
switch (pstate->step_)
{
// ExSamp_CANCELLED
//
// Transition to this state from ...
// 1. ExSamp_Error - After the error has been processed.
// 2. ExSamp_Working - If enough rows have been returned.
// 3. ExSamp_Working - If the request was cancelled.
//
// Remain in this state until ..
// 1. All rows from the child including EOD are consumed
//
// Transition from this state to ...
// 1. ExSamp_DONE - In all cases.
//
case ExSamp_CANCELLED:
{
// There are no extra rows to process from the child yet,
// so try again later.
//
if (qchild_.up->isEmpty())
{
return WORK_OK;
}
ex_queue_entry * centry = qchild_.up->getHeadEntry();
ex_queue::up_status child_status = centry->upState.status;
// If this is the EOD, transition to the ExSamp_DONE state.
//
if (child_status == ex_queue::Q_NO_DATA)
pstate->step_ = ExSamp_DONE;
// Discard the child row.
qchild_.up->removeHead();
break;
}
// ExSamp_ERROR
//
// Transition to this state from ...
// 1. ExSamp_WORKING - a child reply with the type SQLERROR.
//
// Remain in this state until ..
// 1. The error row has been returned to the parent.
//
// Transition from this state to ...
// 1. ExSamp_CANCELLED - In all cases.
//
case ExSamp_ERROR:
{
// If there is no room in the parent queue for the reply,
// try again later.
//
if (qparent_.up->isFull())
return WORK_OK;
ex_queue_entry *pentry_up = qparent_.up->getTailEntry();
ex_queue_entry * centry = qchild_.up->getHeadEntry();
// Cancel the child request - there must be a child request in
// progress to get to the ExSamp_ERROR state.
//
qchild_.down->cancelRequestWithParentIndex
(qparent_.down->getHeadIndex());
// Construct and return the error row.
//
pentry_up->copyAtp(centry);
pentry_up->upState.status = ex_queue::Q_SQLERROR;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex = qparent_.down->getHeadIndex();
pentry_up->upState.setMatchNo(pstate->matchCount_);
qparent_.up->insert();
// Transition to the ExSamp_CANCELLED state.
//
pstate->step_ = ExSamp_CANCELLED;
break;
}
// ExSamp_WORKING
//
// Transition to this state from ...
// 1. ExSamp_EMPTY - If a request is started.
//
// Remain in this state until ...
// 1. All child replies including EOD have been processed.
// 2. A SQLERROR row is received.
// 3. Enough rows have been returned.
// 4. The request is cancelled.
//
// Transition from this state to ...
// 1. ExSamp_DONE - If all the child rows including EOD have
// been processed.
// 2. ExSamp_ERROR - If an SQLERROR rows is received.
// 3. ExSamp_CANCELLED - If enough rows have been returned.
// 3. ExSamp_CANCELLED - If the request is cancelled.
//
case ExSamp_WORKING:
{
// If there is not room in the parent Queue for the reply,
// try again later.
//
if (qparent_.up->isFull())
return WORK_OK;
// If there are no replies, try again later.
//
if (qchild_.up->isEmpty())
return WORK_OK;
ex_queue_entry * centry = qchild_.up->getHeadEntry();
switch (centry->upState.status)
{
// A data row from the child.
//
case ex_queue::Q_OK_MMORE:
{
// Apply the sampling predicate if it exists and extract
// the sampling factor.
//
ex_expr::exp_return_type retCode = ex_expr::EXPR_TRUE;
Int32 samplingFactor = 1;
if(balanceExpr())
{
retCode = balanceExpr()->eval
(centry->getAtp(), centry->getAtp());
if(retCode == ex_expr::EXPR_OK)
{
samplingFactor =
*(Lng32*)balanceExpr()->getPersistentData
(returnFactorOffset());
// If the sampling factor is less than 0, then
// we are done with this request. Mark the
// request as get-no-more. Forces the child to be
// cancelled
//
if(samplingFactor < 0)
{
// Cancel the rest of this
// request.
pentry_down->downState.request
= ex_queue::GET_NOMORE;
request = ex_queue::GET_NOMORE;
// Return no rows
retCode = ex_expr::EXPR_FALSE;
}
}
}
// If the row passed the sampling predicate, apply the
// selection predicate if it exists.
//
if ((samplingFactor > 0) &&
(retCode == ex_expr::EXPR_OK) &&
postPred())
retCode = postPred()->eval
(centry->getAtp(), centry->getAtp());
// Act on the result of the selection predicate.
//
switch(retCode) {
// If the selection predicate returns TRUE,
// return the row to the parent the number
// of times indicated by the sampling factor as long
// as there is room in the parent queue.
//
case ex_expr::EXPR_TRUE:
case ex_expr::EXPR_OK:
while(!qparent_.up->isFull() && (samplingFactor > 0))
{
// Copy the child ATP to the parent ATP -- the
// row images are exactly the same.
//
ex_queue_entry * pentry_up
= qparent_.up->getTailEntry();
pentry_up->copyAtp(centry);
// Fixup the up state.
//
pentry_up->upState.status = ex_queue::Q_OK_MMORE;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex
= qparent_.down->getHeadIndex();
pstate->matchCount_++;
pentry_up->upState.setMatchNo(pstate->matchCount_);
// Commit the entry.
//
qparent_.up->insert();
if (statsEntry)
statsEntry->incActualRowsReturned();
samplingFactor--;
// If we have satisfied a GET_N request, then
// break out of here so we can stop processing.
//
if((request == ex_queue::GET_N) &&
(pentry_down->downState.requestValue
<= (Lng32)pstate->matchCount_))
{
samplingFactor = 0;
break;
}
}
// If all of the rows are returned, then we are done
// with this entry and can proceed.
//
if(samplingFactor == 0)
{
qchild_.up->removeHead();
}
// Otherwise, the queue must have become full so we
// have to switch to the RETURNINGROWS state to finish
// the job.
else
{
pstate->rowsToReturn_ = samplingFactor;
pstate->step_ = ExSamp_RETURNINGROWS;
return WORK_OK;
}
break;
// If the selection predicate returns FALSE,
// do not return the child row.
//
case ex_expr::EXPR_FALSE:
qchild_.up->removeHead();
break;
// If the selection predicate returns an ERROR,
// go to the error processing state.
//
case ex_expr::EXPR_ERROR:
pstate->step_ = ExSamp_ERROR;
break;
}
}
break;
// The EOD from the child. Transition to ExSamp_DONE.
//
case ex_queue::Q_NO_DATA:
pstate->step_ = ExSamp_DONE;
qchild_.up->removeHead();
break;
// An SQLERROR from the child. Transition to ExSamp_ERROR.
//
case ex_queue::Q_SQLERROR:
pstate->step_ = ExSamp_ERROR;
break;
}
}
break;
// ExSamp_RETURNINGROWS
//
// Transistion to this state from ...
// 1. ExSamp_WORKING - if up queue becomes full when returning
// multiple rows from oversampling.
//
// Remain in this state until ...
// 1. the multiple oversampled rows have been returned.
//
case ExSamp_RETURNINGROWS:
{
ex_queue_entry * centry = qchild_.up->getHeadEntry();
while(!qparent_.up->isFull() && (pstate->rowsToReturn_ > 0))
{
// Copy the child ATP to the parent ATP -- the row
// images are exactly the same.
//
ex_queue_entry * pentry_up = qparent_.up->getTailEntry();
pentry_up->copyAtp(centry);
// Fixup the up state.
//
pentry_up->upState.status = ex_queue::Q_OK_MMORE;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex = qparent_.down->getHeadIndex();
pstate->matchCount_++;
pentry_up->upState.setMatchNo(pstate->matchCount_);
// Commit the entry.
//
qparent_.up->insert();
if (statsEntry)
statsEntry->incActualRowsReturned();
pstate->rowsToReturn_--;
// If we have satisfied a GET_N request, then
// break out of here so we can stop processing.
//
if((request == ex_queue::GET_N) &&
(pentry_down->downState.requestValue
<= (Lng32)pstate->matchCount_))
{
pstate->rowsToReturn_ = 0;
break;
}
}
// If all of the rows were returned, remove the child's reply
// and go back to the WORKING state.
//
if(pstate->rowsToReturn_ == 0)
{
qchild_.up->removeHead();
pstate->step_ = ExSamp_WORKING;
}
// Otherwise, we need to come back later to finish up.
//
else
{
return WORK_OK;
}
}
break;
// ExSamp_DONE
//
// Transition to the state from ...
// 1. ExSamp_WORKING - if all child rows have been processed.
// 2. ExSamp_CANCELLED - if all child rows have been consumed.
// 3. ExSamp_EMPTY - if the request was DOA.
//
// Remain in this state until ...
// 1. The EOD is returned to the parent.
//
// Transition from this state to ...
// 1. ExSamp_EMPTY - In all cases.
//
case ExSamp_DONE:
{
// If there is not any room in the parent's queue,
// try again later.
//
if (qparent_.up->isFull())
return WORK_OK;
ex_queue_entry * pentry_up = qparent_.up->getTailEntry();
pentry_up->upState.status = ex_queue::Q_NO_DATA;
pentry_up->upState.parentIndex
= pentry_down->downState.parentIndex;
pentry_up->upState.downIndex = qparent_.down->getHeadIndex();
pentry_up->upState.setMatchNo(pstate->matchCount_);
qparent_.down->removeHead();
qparent_.up->insert();
// Re-initialize pstate
//
pstate->step_ = ExSamp_EMPTY;
pstate->matchCount_ = 0;
pstate->rowsToReturn_ = 0;
pstate->workAtp_->release();
// If there are no more requests, simply return.
//
if (qparent_.down->isEmpty())
return WORK_OK;
// If we haven't given to our child the new head
// index return and ask to be called again.
//
if (qparent_.down->getHeadIndex() == processedInputs_)
return WORK_CALL_AGAIN;
// Postion at the new head of the request queue.
//
pentry_down = qparent_.down->getHeadEntry();
pstate = (ExSamplePrivateState*) pentry_down->pstate;
request = pentry_down->downState.request;
// If the request has not been worked on yet, then initialize the
// presistent expression variable data and switch to the
// WORKING state.
//
if(pstate->step_ == ExSamp_PREWORK)
{
pstate->step_ = ExSamp_WORKING;
if(balanceExpr()) balanceExpr()->initializePersistentData();
}
}
break;
} // switch pstate->step_
} // while
}
