void
RelSequence::addCancelExpr(CollHeap *wHeap)
{
ItemExpr *cPred = NULL;
if (this->partition().entries() > 0)
{
return;
}
if(cancelExpr().entries() > 0)
{
return;
}
for(ValueId valId = selectionPred().init();
selectionPred().next(valId);
selectionPred().advance(valId))
{
ItemExpr *pred = valId.getItemExpr();
// Look for preds that select a prefix of the sequence.
// Rank() < const; Rank <= const; const > Rank; const >= Rank
ItemExpr *op1 = NULL;
ItemExpr *op2 = NULL;
if(pred->getOperatorType() == ITM_LESS ||
pred->getOperatorType() == ITM_LESS_EQ)
{
op1 = pred->child(0);
op2 = pred->child(1);
}
else if (pred->getOperatorType() == ITM_GREATER ||
pred->getOperatorType() == ITM_GREATER_EQ)
{
op1 = pred->child(1);
op2 = pred->child(0);
}
NABoolean negate;
if (op1 && op2 &&
(op2->getOperatorType() == ITM_CONSTANT ||
op2->getOperatorType() == ITM_DYN_PARAM) &&
(op1->getOperatorType() == ITM_OLAP_RANK ||
op1->getOperatorType() == ITM_OLAP_DRANK ||
(op1->getOperatorType() == ITM_OLAP_COUNT &&
op1->child(0)->getOperatorType() == ITM_CONSTANT &&
!op1->child(0)->castToConstValue(negate)->isNull())))
{
cPred = new(wHeap) UnLogic(ITM_NOT, pred);
//break at first occurence
break;
}
}
if(cPred)
{
cPred->synthTypeAndValueId(TRUE);
cancelExpr().insert(cPred->getValueId());
}
}
HashValue MultiJoin::topHash()
{
selectionPred().clear();
HashValue result = RelExpr::topHash();
result ^= jbbSubset_.getJBBCs();
result ^= CollIndex(jbbSubset_.getGB());
return result;
}
// change literals of a cacheable query into ConstantParameters
RelExpr* RelExpr::normalizeForCache(CacheWA& cwa, BindWA& bindWA)
{
if (nodeIsNormalizedForCache()) {
return this;
}
// replace descendants' literals into ConstantParameters
normalizeKidsForCache(cwa, bindWA);
if (cwa.getPhase() >= CmpMain::BIND) {
if (selection_) {
selection_ = selection_->normalizeForCache(cwa, bindWA);
}
else {
selectionPred().normalizeForCache(cwa, bindWA);
}
// RelExpr::bindSelf has done this line during binding; but, we
// must redo it to recognize any new constantparameters created
// by the above normalizeForCache call(s) as RelExpr inputs.
getGroupAttr()->addCharacteristicInputs
(bindWA.getCurrentScope()->getOuterRefs());
}
markAsNormalizedForCache();
return this;
}
short ProbeCache::codeGen(Generator *generator)
{
ExpGenerator * exp_gen = generator->getExpGenerator();
Space * space = generator->getSpace();
MapTable * last_map_table = generator->getLastMapTable();
ex_cri_desc * given_desc
= generator->getCriDesc(Generator::DOWN);
ex_cri_desc * returned_desc
= new(space) ex_cri_desc(given_desc->noTuples() + 1, space);
// cri descriptor for work atp has 5 entries:
// entry #0 for const
// entry #1 for temp
// entry #2 for hash value of probe input data in Probe Cache Manager
// entry #3 for encoded probe input data in Probe Cache Manager
// enrry #4 for inner table row data in this operator's cache buffer
Int32 work_atp = 1;
ex_cri_desc * work_cri_desc = new(space) ex_cri_desc(5, space);
unsigned short hashValIdx = 2;
unsigned short encodedProbeDataIdx = 3;
unsigned short innerRowDataIdx = 4;
// generate code for child tree, and get its tdb and explain tuple.
child(0)->codeGen(generator);
ComTdb * child_tdb = (ComTdb *)(generator->getGenObj());
ExplainTuple *childExplainTuple = generator->getExplainTuple();
//////////////////////////////////////////////////////
// Generate up to 4 runtime expressions.
//////////////////////////////////////////////////////
// Will use child's char. inputs (+ execution count) for the next
// two runtime expressions.
ValueIdList inputsToUse = child(0).getGroupAttr()->getCharacteristicInputs();
inputsToUse.insert(generator->getOrAddStatementExecutionCount());
// Expression #1 gets the hash value of the probe input data
ValueIdList hvAsList;
// Executor has hard-coded assumption that the result is long,
// so add a Cast node to convert result to a long.
ItemExpr *probeHashAsIe = new (generator->wHeap())
HashDistPartHash(inputsToUse.rebuildExprTree(ITM_ITEM_LIST));
probeHashAsIe->bindNode(generator->getBindWA());
NumericType &nTyp = (NumericType &)probeHashAsIe->getValueId().getType();
GenAssert(nTyp.isSigned() == FALSE,
"Unexpected signed HashDistPartHash.");
GenAssert(probeHashAsIe->getValueId().getType().supportsSQLnullLogical()
== FALSE, "Unexpected nullable HashDistPartHash.");
ItemExpr *hvAsIe = new (generator->wHeap()) Cast(
probeHashAsIe,
new (generator->wHeap())
SQLInt(FALSE, // false == unsigned.
FALSE // false == not nullable.
));
hvAsIe->bindNode(generator->getBindWA());
hvAsList.insert(hvAsIe->getValueId());
ex_expr *hvExpr = NULL;
ULng32 hvLength;
exp_gen->generateContiguousMoveExpr(
hvAsList,
0, // don't add convert node
work_atp,
hashValIdx,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
hvLength,
&hvExpr);
GenAssert(hvLength == sizeof(Lng32),
"Unexpected length of result of hash function.");
// Expression #2 encodes the probe input data for storage in
// the ProbeCacheManager.
ValueIdList encodeInputAsList;
CollIndex inputListIndex;
for (inputListIndex = 0;
inputListIndex < inputsToUse.entries();
inputListIndex++) {
ItemExpr *inputIe =
(inputsToUse[inputListIndex].getValueDesc())->getItemExpr();
if (inputIe->getValueId().getType().getVarLenHdrSize() > 0)
{
// This logic copied from Sort::codeGen().
// Explode varchars by moving them to a fixed field
// whose length is equal to the max length of varchar.
// 5/8/98: add support for VARNCHAR
const CharType& char_type =
(CharType&)(inputIe->getValueId().getType());
if (!CollationInfo::isSystemCollation(char_type.getCollation()))
{
inputIe = new(generator->wHeap())
Cast (inputIe,
(new(generator->wHeap())
SQLChar(
CharLenInfo(char_type.getStrCharLimit(), char_type.getDataStorageSize()),
char_type.supportsSQLnull(),
FALSE, FALSE, FALSE,
char_type.getCharSet(),
char_type.getCollation(),
char_type.getCoercibility()
)
)
);
}
}
CompEncode * enode = new(generator->wHeap())
CompEncode(inputIe, FALSE /* ascend/descend doesn't matter*/);
enode->bindNode(generator->getBindWA());
encodeInputAsList.insert(enode->getValueId());
}
ex_expr *encodeInputExpr = NULL;
ULng32 encodedInputLength;
exp_gen->generateContiguousMoveExpr(encodeInputAsList,
0, //don't add conv nodes
work_atp, encodedProbeDataIdx,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
encodedInputLength, &encodeInputExpr);
// Expression #3 moves the inner table data into a buffer pool.
// This is also the tuple returned to ProbeCache's parent.
ex_expr * innerRecExpr = NULL;
ValueIdList innerTableAsList = getGroupAttr()->getCharacteristicOutputs();
//////////////////////////////////////////////////////
// Describe the returned row and add the returned
// values to the map table.
//////////////////////////////////////////////////////
// determine internal format
NABoolean useCif = FALSE;
ExpTupleDesc::TupleDataFormat tupleFormat = generator->getInternalFormat();
//tupleFormat = determineInternalFormat( innerTableAsList, this, useCif,generator);
ULng32 innerRecLength = 0;
ExpTupleDesc * innerRecTupleDesc = 0;
MapTable * returnedMapTable = NULL;
exp_gen->generateContiguousMoveExpr(innerTableAsList,
-1, // do add conv nodes
work_atp, innerRowDataIdx,
tupleFormat,
innerRecLength, &innerRecExpr,
&innerRecTupleDesc, ExpTupleDesc::SHORT_FORMAT,
&returnedMapTable);
returned_desc->setTupleDescriptor(returned_desc->noTuples() - 1,
innerRecTupleDesc);
// remove all appended map tables and return the returnedMapTable
generator->removeAll(last_map_table);
generator->appendAtEnd(returnedMapTable);
// This returnedMapTable will contain the value ids that are being returned
// (the inner table probed).
// Massage the atp and atp_index of the innerTableAsList.
for (CollIndex i = 0; i < innerTableAsList.entries(); i++)
{
ValueId innerValId = innerTableAsList[i];
Attributes *attrib =
generator->getMapInfo(innerValId)->getAttr();
// All reference to the returned values from this point on
// will be at atp = 0, atp_index = last entry in returned desc.
attrib->setAtp(0);
attrib->setAtpIndex(returned_desc->noTuples() - 1);
}
// Expression #4 is a selection predicate, to be applied
// before returning rows to the parent
ex_expr * selectPred = NULL;
if (!selectionPred().isEmpty())
{
ItemExpr * selPredTree =
selectionPred().rebuildExprTree(ITM_AND,TRUE,TRUE);
exp_gen->generateExpr(selPredTree->getValueId(),
ex_expr::exp_SCAN_PRED,
&selectPred);
}
//////////////////////////////////////////////////////
// Prepare params for ComTdbProbeCache.
//////////////////////////////////////////////////////
queue_index pDownSize = (queue_index)getDefault(GEN_PROBE_CACHE_SIZE_DOWN);
queue_index pUpSize = (queue_index)getDefault(GEN_PROBE_CACHE_SIZE_UP);
// Make sure that the ProbeCache queues can support the childs queues.
if(pDownSize < child_tdb->getInitialQueueSizeDown()) {
pDownSize = child_tdb->getInitialQueueSizeDown();
pDownSize = MINOF(pDownSize, 32768);
}
if(pUpSize < child_tdb->getInitialQueueSizeUp()) {
pUpSize = child_tdb->getInitialQueueSizeUp();
pUpSize = MINOF(pUpSize, 32768);
}
ULng32 pcNumEntries = numCachedProbes_;
// Number of entries in the probe cache cannot be less than
// max parent down queue size. Before testing and adjusting the
// max queue size, it is necessary to make sure it is a power of
// two, rounding up if necessary. This is to match the logic in
// ex_queue::resize.
queue_index pdq2 = 1;
queue_index bits = pDownSize;
while (bits && pdq2 < pDownSize) {
bits = bits >> 1;
pdq2 = pdq2 << 1;
}
if (pcNumEntries < pdq2)
pcNumEntries = pdq2;
numInnerTuples_ = getDefault(GEN_PROBE_CACHE_NUM_INNER);
if (innerRecExpr == NULL)
{
// For semi-join and anti-semi-join, executor need not allocate
// a buffer. Set the tdb's buffer size to 0 to be consistent.
numInnerTuples_ = 0;
}
else if (numInnerTuples_ == 0)
{
// Handle special value, 0, which tells code gen to
// decided on buffer size: i.e., large enough to accomodate
// all parent up queue entries and all probe cache entries
// having a different inner table row.
// As we did for the down queue, make sure the up queue size
// specified is a power of two.
queue_index puq2 = 1;
queue_index bits = pUpSize;
while (bits && puq2 < pUpSize) {
bits = bits >> 1;
puq2 = puq2 << 1;
}
numInnerTuples_ = puq2 + pcNumEntries;
}
short RelInternalSP::codeGen(Generator * generator)
{
Space * space = generator->getSpace();
ExpGenerator * exp_gen = generator->getExpGenerator();
MapTable * last_map_table = generator->getLastMapTable();
ex_expr * input_expr = NULL;
ex_expr * output_expr = NULL;
////////////////////////////////////////////////////////////////////////////
//
// Returned atp layout:
//
// |--------------------------------|
// | input data | stored proc row |
// | ( I tupps ) | ( 1 tupp ) |
// |--------------------------------|
// <-- returned row to parent ---->
//
// input data: the atp input to this node by its parent.
// stored proc row: tupp where the row read from SP is moved.
//
////////////////////////////////////////////////////////////////////////////
ex_cri_desc * given_desc
= generator->getCriDesc(Generator::DOWN);
ex_cri_desc * returned_desc
= new(space) ex_cri_desc(given_desc->noTuples() + 1, space);
// cri descriptor for work atp has 3 entries:
// -- the first two entries for consts and temps.
// -- Entry 3(index #2) is where the input and output rows will be created.
ex_cri_desc * work_cri_desc = new(space) ex_cri_desc(3, space);
const Int32 work_atp = 1;
const Int32 work_atp_index = 2;
ExpTupleDesc * input_tuple_desc = NULL;
ExpTupleDesc * output_tuple_desc = NULL;
// Generate expression to create the input row that will be
// given to the stored proc.
// The input value is in sp->getProcAllParams()
// and has to be converted to sp->procType().
// Generate Cast node to convert procParam to ProcType.
// If procType is a varchar, explode it. This is done
// so that values could be extracted correctly.
ValueIdList procVIDList;
for (CollIndex i = 0; i < procTypes().entries(); i++)
{
Cast * cn;
if ((procTypes())[i].getType().getVarLenHdrSize() > 0)
{
// 5/9/98: add support for VARNCHAR
const CharType& char_type =
(CharType&)((procTypes())[i].getType());
// Explode varchars by moving them to a fixed field
// whose length is equal to the max length of varchar.
cn = new(generator->wHeap())
Cast ((getProcAllParamsVids())[i].getItemExpr(),
(new(generator->wHeap())
SQLChar(generator->wHeap(),
CharLenInfo(char_type.getStrCharLimit(), char_type.getDataStorageSize()),
char_type.supportsSQLnull(),
FALSE, FALSE, FALSE,
char_type.getCharSet(),
char_type.getCollation(),
char_type.getCoercibility()
/*
(procTypes())[i].getType().getNominalSize(),
(procTypes())[i].getType().supportsSQLnull()
*/
)
)
);
// Move the exploded field to a varchar field since
// procType is varchar.
// Can optimize by adding an option to convert node to
// blankpad. TBD.
//
cn = new(generator->wHeap())
Cast(cn, &((procTypes())[i].getType()));
}
else
cn = new(generator->wHeap()) Cast((getProcAllParamsVids())[i].getItemExpr(),
&((procTypes())[i].getType()));
cn->bindNode(generator->getBindWA());
procVIDList.insert(cn->getValueId());
}
ULng32 inputRowlen_ = 0;
exp_gen->generateContiguousMoveExpr(procVIDList, -1, /*add conv nodes*/
work_atp, work_atp_index,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
inputRowlen_,
&input_expr,
&input_tuple_desc,
ExpTupleDesc::LONG_FORMAT);
// add all columns from this SP to the map table.
ULng32 tupleLength;
exp_gen->processValIdList(getTableDesc()->getColumnList(),
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
tupleLength,
work_atp,
work_atp_index);
// Generate expression to move the output row returned by the
// stored proc back to parent.
ULng32 outputRowlen_ = 0;
MapTable * returnedMapTable = 0;
exp_gen->generateContiguousMoveExpr(getTableDesc()->getColumnList(),
-1 /*add conv nodes*/,
0, returned_desc->noTuples() - 1,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
outputRowlen_,
&output_expr,
&output_tuple_desc,
ExpTupleDesc::LONG_FORMAT,
&returnedMapTable);
// Now generate expressions used to extract or move input or
// output values. See class ExSPInputOutput.
ExSPInputOutput * extractInputExpr = NULL;
ExSPInputOutput * moveOutputExpr = NULL;
generateSPIOExpr(this, generator,
extractInputExpr,
moveOutputExpr);
// done with expressions at this operator. Remove the appended map tables.
generator->removeAll(last_map_table);
// append the map table containing the returned columns
generator->appendAtEnd(returnedMapTable);
NAString procNameAsNAString(procName_);
char * sp_name =
space->allocateAndCopyToAlignedSpace(procNameAsNAString,
procNameAsNAString.length(), 0);
ExpGenerator *expGen = generator->getExpGenerator();
// expression to conditionally return 0 or more rows.
ex_expr *predExpr = NULL;
// generate tuple selection expression, if present
if(NOT selectionPred().isEmpty())
{
ItemExpr* pred = selectionPred().rebuildExprTree(ITM_AND,TRUE,TRUE);
expGen->generateExpr(pred->getValueId(),ex_expr::exp_SCAN_PRED,&predExpr);
}
ComTdbStoredProc * sp_tdb = new(space)
ComTdbStoredProc(sp_name,
input_expr,
inputRowlen_,
output_expr,
outputRowlen_,
work_cri_desc,
work_atp_index,
given_desc,
returned_desc,
extractInputExpr,
moveOutputExpr,
2,
1024,
(Cardinality) getGroupAttr()->
getOutputLogPropList()[0]->
getResultCardinality().value(),
5,
64000, //10240
predExpr,
(UInt16) arkcmpInfo_);
generator->initTdbFields(sp_tdb);
if(!generator->explainDisabled())
{
generator->setExplainTuple(
addExplainInfo(sp_tdb, 0, 0, generator));
}
// Do not infer that any transaction started can
// be in READ ONLY mode if ISPs are present.
generator->setNeedsReadWriteTransaction(TRUE);
generator->setCriDesc(given_desc, Generator::DOWN);
generator->setCriDesc(returned_desc, Generator::UP);
generator->setGenObj(this, sp_tdb);
// Some built-in functions require a TMF transaction
// because they get their information from catman
generator->setTransactionFlag(getRequiresTMFTransaction());
return 0;
}
// PhysUnPackRows::preCodeGen() -------------------------------------------
// Perform local query rewrites such as for the creation and
// population of intermediate tables, for accessing partitioned
// data. Rewrite the value expressions after minimizing the dataflow
// using the transitive closure of equality predicates.
//
// PhysUnPackRows::preCodeGen() - is basically the same as the RelExpr::
// preCodeGen() except that here we replace the VEG references in the
// unPackExpr() and packingFactor(), as well as the selectionPred().
//
// Parameters:
//
// Generator *generator
// IN/OUT : A pointer to the generator object which contains the state,
// and tools (e.g. expression generator) to generate code for
// this node.
//
// ValueIdSet &externalInputs
// IN : The set of external Inputs available to this node.
//
//
RelExpr * PhysUnPackRows::preCodeGen(Generator * generator,
const ValueIdSet & externalInputs,
ValueIdSet &pulledNewInputs)
{
if (nodeIsPreCodeGenned())
return this;
// Resolve the VEGReferences and VEGPredicates, if any, that appear
// in the Characteristic Inputs, in terms of the externalInputs.
//
getGroupAttr()->resolveCharacteristicInputs(externalInputs);
// My Characteristic Inputs become the external inputs for my children.
//
ValueIdSet childPulledInputs;
child(0) = child(0)->preCodeGen(generator, externalInputs, pulledNewInputs);
if (! child(0).getPtr())
return NULL;
// process additional input value ids the child wants
getGroupAttr()->addCharacteristicInputs(childPulledInputs);
pulledNewInputs += childPulledInputs;
// The VEG expressions in the selection predicates and the characteristic
// outputs can reference any expression that is either a potential output
// or a characteristic input for this RelExpr. Supply these values for
// rewriting the VEG expressions.
//
ValueIdSet availableValues;
getInputValuesFromParentAndChildren(availableValues);
// The unPackExpr() and packingFactor() expressions have access
// to only the Input Values. These can come from the parent or be
// the outputs of the child.
//
unPackExpr().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
packingFactor().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
if (rowwiseRowset())
{
if (rwrsInputSizeExpr())
((ItemExpr*)rwrsInputSizeExpr())->
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
if (rwrsMaxInputRowlenExpr())
((ItemExpr*)rwrsMaxInputRowlenExpr())->
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
if (rwrsBufferAddrExpr())
((ItemExpr*)rwrsBufferAddrExpr())->
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
}
// The selectionPred has access to only the output values generated by
// UnPackRows and input values from the parent.
//
getInputAndPotentialOutputValues(availableValues);
// Rewrite the selection predicates.
//
NABoolean replicatePredicates = TRUE;
selectionPred().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs(),
FALSE, // no key predicates here
0 /* no need for idempotence here */,
replicatePredicates
);
// Replace VEG references in the outputs and remove redundant
// outputs.
//
getGroupAttr()->resolveCharacteristicOutputs
(availableValues,
getGroupAttr()->getCharacteristicInputs());
generator->oltOptInfo()->setMultipleRowsReturned(TRUE);
markAsPreCodeGenned();
return this;
} // PhysUnPackRows::preCodeGen
short
PhysUnPackRows::codeGen(Generator *generator)
{
// Get handles on expression generator, map table, and heap allocator
//
ExpGenerator *expGen = generator->getExpGenerator();
Space *space = generator->getSpace();
// Allocate a new map table for this operation
//
MapTable *localMapTable = generator->appendAtEnd();
// Generate the child and capture the task definition block and a description
// of the reply composite row layout and the explain information.
//
child(0)->codeGen(generator);
ComTdb *childTdb = (ComTdb*)(generator->getGenObj());
ex_cri_desc *childCriDesc = generator->getCriDesc(Generator::UP);
ExplainTuple *childExplainTuple = generator->getExplainTuple();
// Make all of my child's outputs map to ATP 1. Since they are
// not needed above, they will not be in the work ATP (0).
// (Later, they will be removed from the map table)
//
localMapTable->setAllAtp(1);
// Generate the given and returned composite row descriptors.
// unPackRows adds a tupp (for the generated outputs) to the
// row given by the parent. The workAtp will have the 2 more
// tupps (1 for the generated outputs and another for the
// indexValue) than the given.
//
ex_cri_desc *givenCriDesc = generator->getCriDesc(Generator::DOWN);
ex_cri_desc *returnedCriDesc =
#pragma nowarn(1506) // warning elimination
new(space) ex_cri_desc(givenCriDesc->noTuples() + 1, space);
#pragma warn(1506) // warning elimination
ex_cri_desc *workCriDesc =
#pragma nowarn(1506) // warning elimination
new(space) ex_cri_desc(givenCriDesc->noTuples() + 2, space);
#pragma warn(1506) // warning elimination
// unPackCols is the next to the last Tp in Atp 0, the work ATP.
// and the last Tp in the returned ATP.
//
const Int32 unPackColsAtpIndex = workCriDesc->noTuples() - 2;
const Int32 unPackColsAtp = 0;
// The length of the new tuple which will contain the columns
// generated by unPackRows
//
ULng32 unPackColsTupleLen;
// The Tuple Desc describing the tuple containing the new unPacked columns
// It is generated when the expression is generated.
//
ExpTupleDesc *unPackColsTupleDesc = 0;
// indexValue is the last Tp in Atp 0, the work ATP.
//
const Int32 indexValueAtpIndex = workCriDesc->noTuples() - 1;
const Int32 indexValueAtp = 0;
// The length of the work tuple which will contain the value
// of the index. This should always be sizeof(int).
//
ULng32 indexValueTupleLen = 0;
// The Tuple Desc describing the tuple containing the new unPacked columns
// It is generated when the expression is generated.
//
ExpTupleDesc *indexValueTupleDesc = 0;
ValueIdList indexValueList;
if (indexValue() != NULL_VALUE_ID)
{
indexValueList.insert(indexValue());
expGen->processValIdList(indexValueList,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
indexValueTupleLen,
indexValueAtp,
indexValueAtpIndex,
&indexValueTupleDesc,
ExpTupleDesc::SHORT_FORMAT);
GenAssert(indexValueTupleLen == sizeof(Int32),
"UnPackRows::codeGen: Internal Error");
}
// If a packingFactor exists, generate a move expression for this.
// It is assumed that the packingFactor expression evaluates to a
// 4 byte integer.
//
ex_expr *packingFactorExpr = 0;
ULng32 packingFactorTupleLen;
if(packingFactor().entries() > 0) {
expGen->generateContiguousMoveExpr(packingFactor(),
-1,
unPackColsAtp,
unPackColsAtpIndex,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
packingFactorTupleLen,
&packingFactorExpr);
GenAssert(packingFactorTupleLen == sizeof(Int32),
"UnPackRows::codeGen: Internal Error");
}
// Generate the UnPack expressions.
//
// characteristicOutputs() - refers to the list of expressions
// to be move to another tuple.
//
// 0 - Do not add conv. nodes.
//
// unPackColsAtp - this expression will move data to the
// unPackColsAtp (0) ATP.
//
// unPackColsAtpIndex - within the unPackColsAtp (0) ATP, the destination
// for this move expression will be the unPackColsAtpIndex TP. This should
// be the next to the last TP of the work ATP. (The indexValue will be in
// the last position)
//
// SQLARK_EXPLODED_FORMAT - generate the move expression to construct
// the destination tuple in EXPLODED FORMAT.
//
// unPackColsTupleLen - This is an output which will contain the length
// of the destination Tuple.
//
// &unPackColsExpr - The address of the pointer to the expression
// which will be generated.
//
// &unPackColsTupleDesc - The address of the tuple descriptor which is
// generated. This describes the destination tuple of the move expression.
//
// SHORT_FORMAT - generate the unPackColsTupleDesc in the SHORT FORMAT.
//
ex_expr *unPackColsExpr = 0;
expGen->
genGuardedContigMoveExpr(selectionPred(),
getGroupAttr()->getCharacteristicOutputs(),
0, // No Convert Nodes added
unPackColsAtp,
unPackColsAtpIndex,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
unPackColsTupleLen,
&unPackColsExpr,
&unPackColsTupleDesc,
ExpTupleDesc::SHORT_FORMAT);
#pragma nowarn(1506) // warning elimination
workCriDesc->setTupleDescriptor(unPackColsAtpIndex,
#pragma warn(1506) // warning elimination
unPackColsTupleDesc);
#pragma nowarn(1506) // warning elimination
returnedCriDesc->setTupleDescriptor(unPackColsAtpIndex,
#pragma warn(1506) // warning elimination
unPackColsTupleDesc);
// expressions for rowwise rowset implementation.
ex_expr * rwrsInputSizeExpr = 0;
ex_expr * rwrsMaxInputRowlenExpr = 0;
ex_expr * rwrsBufferAddrExpr = 0;
ULng32 rwrsInputSizeExprLen = 0;
ULng32 rwrsMaxInputRowlenExprLen = 0;
ULng32 rwrsBufferAddrExprLen = 0;
const Int32 rwrsAtp = 1;
const Int32 rwrsAtpIndex = workCriDesc->noTuples() - 2;
ExpTupleDesc * rwrsTupleDesc = 0;
ValueIdList rwrsVidList;
if (rowwiseRowset())
{
rwrsVidList.insert(this->rwrsInputSizeExpr()->getValueId());
expGen->generateContiguousMoveExpr(rwrsVidList,
0 /*don't add conv nodes*/,
rwrsAtp, rwrsAtpIndex,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
rwrsInputSizeExprLen,
&rwrsInputSizeExpr,
&rwrsTupleDesc,ExpTupleDesc::SHORT_FORMAT);
rwrsVidList.clear();
rwrsVidList.insert(this->rwrsMaxInputRowlenExpr()->getValueId());
expGen->generateContiguousMoveExpr(rwrsVidList,
0 /*don't add conv nodes*/,
rwrsAtp, rwrsAtpIndex,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
rwrsMaxInputRowlenExprLen,
&rwrsMaxInputRowlenExpr,
&rwrsTupleDesc,ExpTupleDesc::SHORT_FORMAT);
rwrsVidList.clear();
rwrsVidList.insert(this->rwrsBufferAddrExpr()->getValueId());
expGen->generateContiguousMoveExpr(rwrsVidList,
0 /*don't add conv nodes*/,
rwrsAtp, rwrsAtpIndex,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
rwrsBufferAddrExprLen,
&rwrsBufferAddrExpr,
&rwrsTupleDesc,ExpTupleDesc::SHORT_FORMAT);
expGen->assignAtpAndAtpIndex(rwrsOutputVids(),
unPackColsAtp, unPackColsAtpIndex);
}
// Move the generated maptable entries, to the localMapTable,
// so that all other entries can later be removed.
//
for(ValueId outputValId = getGroupAttr()->getCharacteristicOutputs().init();
getGroupAttr()->getCharacteristicOutputs().next(outputValId);
getGroupAttr()->getCharacteristicOutputs().advance(outputValId)) {
generator->addMapInfoToThis(localMapTable, outputValId,
generator->getMapInfo(outputValId)->
getAttr());
// Indicate that code was generated for this map table entry.
//
generator->getMapInfoFromThis(localMapTable, outputValId)->codeGenerated();
}
NABoolean tolerateNonFatalError = FALSE;
if (isRowsetIterator() && (generator->getTolerateNonFatalError())) {
tolerateNonFatalError = TRUE;
setTolerateNonFatalError(RelExpr::NOT_ATOMIC_);
}
// Allocate the UnPack TDB
//
ComTdbUnPackRows *unPackTdb = NULL;
if (rowwiseRowset())
{
unPackTdb =
new (space) ComTdbUnPackRows(NULL, //childTdb,
rwrsInputSizeExpr,
rwrsMaxInputRowlenExpr,
rwrsBufferAddrExpr,
rwrsAtpIndex,
givenCriDesc,
returnedCriDesc,
workCriDesc,
16,
1024,
(Cardinality) getGroupAttr()->
getOutputLogPropList()[0]->
getResultCardinality().value(),
2, 20000);
}
else
{
// Base the initial queue size on the est. cardinality.
// UnPackRows does not do dyn queue resize, so passed in
// queue size values represent initial (and final) queue
// sizes (not max queue sizes).
//
queue_index upQueueSize =
(queue_index)getGroupAttr()->getOutputLogPropList()[0]->getResultCardinality().value();
// Make sure it is at least 1024.
upQueueSize = (upQueueSize < 1024 ? 1024 : upQueueSize);
// Make sure that it is not more the 64K.
upQueueSize = (upQueueSize > 65536 ? 65536 : upQueueSize);
unPackTdb =
new (space) ComTdbUnPackRows(childTdb,
packingFactorExpr,
unPackColsExpr,
#pragma nowarn(1506) // warning elimination
unPackColsTupleLen,
unPackColsAtpIndex,
indexValueAtpIndex,
givenCriDesc,
returnedCriDesc,
workCriDesc,
16,
upQueueSize,
(Cardinality) getGroupAttr()->
getOutputLogPropList()[0]->
getResultCardinality().value(),
isRowsetIterator(),
tolerateNonFatalError);
}
#pragma warn(1506) // warning elimination
generator->initTdbFields(unPackTdb);
// Remove child's outputs from mapTable, They are not needed
// above.
//
generator->removeAll(localMapTable);
// Add the explain Information for this node to the EXPLAIN
// Fragment. Set the explainTuple pointer in the generator so
// the parent of this node can get a handle on this explainTuple.
//
if(!generator->explainDisabled()) {
generator->setExplainTuple(addExplainInfo(unPackTdb,
childExplainTuple,
0,
generator));
}
// Restore the Cri Desc's and set the return object.
//
generator->setCriDesc(givenCriDesc, Generator::DOWN);
generator->setCriDesc(returnedCriDesc, Generator::UP);
generator->setGenObj(this, unPackTdb);
return 0;
}
short
PhysSequence::codeGen(Generator *generator)
{
// Get a local handle on some of the generator objects.
//
CollHeap *wHeap = generator->wHeap();
Space *space = generator->getSpace();
ExpGenerator *expGen = generator->getExpGenerator();
MapTable *mapTable = generator->getMapTable();
// Allocate a new map table for this node. This must be done
// before generating the code for my child so that this local
// map table will be sandwiched between the map tables already
// generated and the map tables generated by my offspring.
//
// Only the items available as output from this node will
// be put in the local map table. Before exiting this function, all of
// my offsprings map tables will be removed. Thus, none of the outputs
// from nodes below this node will be visible to nodes above it except
// those placed in the local map table and those that already exist in
// my ancestors map tables. This is the standard mechanism used in the
// generator for managing the access to item expressions.
//
MapTable *localMapTable = generator->appendAtEnd();
// Since this operation doesn't modify the row on the way down the tree,
// go ahead and generate the child subtree. Capture the given composite row
// descriptor and the child's returned TDB and composite row descriptor.
//
ex_cri_desc * givenCriDesc = generator->getCriDesc(Generator::DOWN);
child(0)->codeGen(generator);
ComTdb *childTdb = (ComTdb*)generator->getGenObj();
ex_cri_desc * childCriDesc = generator->getCriDesc(Generator::UP);
ExplainTuple *childExplainTuple = generator->getExplainTuple();
// Make all of my child's outputs map to ATP 1. The child row is only
// accessed in the project expression and it will be the second ATP
// (ATP 1) passed to this expression.
//
localMapTable->setAllAtp(1);
// My returned composite row has an additional tupp.
//
Int32 numberTuples = givenCriDesc->noTuples() + 1;
ex_cri_desc * returnCriDesc
#pragma nowarn(1506) // warning elimination
= new (space) ex_cri_desc(numberTuples, space);
#pragma warn(1506) // warning elimination
// For now, the history buffer row looks just the return row. Later,
// it may be useful to add an additional tupp for sequence function
// itermediates that are not needed above this node -- thus, this
// ATP is kept separate from the returned ATP.
//
const Int32 historyAtp = 0;
const Int32 historyAtpIndex = numberTuples-1;
#pragma nowarn(1506) // warning elimination
ex_cri_desc *historyCriDesc = new (space) ex_cri_desc(numberTuples, space);
#pragma warn(1506) // warning elimination
ExpTupleDesc *historyDesc = 0;
//seperate the read and retur expressions
seperateReadAndReturnItems(wHeap);
// The history buffer consists of items projected directly from the
// child, the root sequence functions, the value arguments of the
// offset functions, and running sequence functions. These elements must
// be materialized in the history buffer in order to be able to compute
// the outputs of this node -- the items projected directly from the child
// (projectValues) and the root sequence functions (sequenceFunctions).
//
// Compute the set of sequence function items that must be materialized
// int the history buffer. -- sequenceItems
//
// Compute the set of items in the history buffer: the union of the
// projected values and the value arguments. -- historyIds
//
// Compute the set of items in the history buffer that are computed:
// the difference between all the elements in the history buffer
// and the projected items. -- computedHistoryIds
//
// KB---will need to return atp with 3 tups only 0,1 and 2
// 2 -->values from history buffer after ther are moved to it
addCheckPartitionChangeExpr(generator, TRUE);
ValueIdSet historyIds;
historyIds += movePartIdsExpr();
historyIds += sequencedColumns();
ValueIdSet outputFromChild = child(0)->getGroupAttr()->getCharacteristicOutputs();
getHistoryAttributes(readSeqFunctions(),outputFromChild, historyIds, TRUE, wHeap);
// Add in the top level sequence functions.
historyIds += readSeqFunctions();
getHistoryAttributes(returnSeqFunctions(),outputFromChild, historyIds, TRUE, wHeap);
// Add in the top level functions.
historyIds += returnSeqFunctions();
// Layout the work tuple format which consists of the projected
// columns and the computed sequence functions. First, compute
// the number of attributes in the tuple.
//
ULng32 numberAttributes
= ((NOT historyIds.isEmpty()) ? historyIds.entries() : 0);
// Allocate an attribute pointer vector from the working heap.
//
Attributes **attrs = new(wHeap) Attributes*[numberAttributes];
// Fill in the attributes vector for the history buffer including
// adding the entries to the map table. Also, compute the value ID
// set for the elements to project from the child row.
//
//??????????re-visit this function??
computeHistoryAttributes(generator,
localMapTable,
attrs,
historyIds);
// Create the tuple descriptor for the history buffer row and
// assign the offsets to the attributes. For now, this layout is
// identical to the returned row. Set the tuple descriptors for
// the return and history rows.
//
ULng32 historyRecLen;
expGen->processAttributes(numberAttributes,
attrs,
ExpTupleDesc::SQLARK_EXPLODED_FORMAT,
historyRecLen,
historyAtp,
historyAtpIndex,
&historyDesc,
ExpTupleDesc::SHORT_FORMAT);
NADELETEBASIC(attrs, wHeap);
#pragma nowarn(1506) // warning elimination
returnCriDesc->setTupleDescriptor(historyAtpIndex, historyDesc);
#pragma warn(1506) // warning elimination
#pragma nowarn(1506) // warning elimination
historyCriDesc->setTupleDescriptor(historyAtpIndex, historyDesc);
#pragma warn(1506) // warning elimination
// If there are any sequence function items, generate the sequence
// function expressions.
//
ex_expr * readSeqExpr = NULL;
if(NOT readSeqFunctions().isEmpty())
{
ValueIdSet seqVals = readSeqFunctions();
seqVals += sequencedColumns();
seqVals += movePartIdsExpr();
expGen->generateSequenceExpression(seqVals,
readSeqExpr);
}
ex_expr *checkPartChangeExpr = NULL;
if (!checkPartitionChangeExpr().isEmpty()) {
ItemExpr * newCheckPartitionChangeTree=
checkPartitionChangeExpr().rebuildExprTree(ITM_AND,TRUE,TRUE);
expGen->generateExpr(newCheckPartitionChangeTree->getValueId(),
ex_expr::exp_SCAN_PRED,
&checkPartChangeExpr);
}
//unsigned long rowLength;
ex_expr * returnExpr = NULL;
if(NOT returnSeqFunctions().isEmpty())
{
expGen->generateSequenceExpression(returnSeqFunctions(),
returnExpr);
}
// Generate expression to evaluate predicate on the output
//
ex_expr *postPred = 0;
if (! selectionPred().isEmpty()) {
ItemExpr * newPredTree =
selectionPred().rebuildExprTree(ITM_AND,TRUE,TRUE);
expGen->generateExpr(newPredTree->getValueId(), ex_expr::exp_SCAN_PRED,
&postPred);
}
// Reset ATP's to zero for parent.
//
localMapTable->setAllAtp(0);
// Generate expression to evaluate the cancel expression
//
ex_expr *cancelExpression = 0;
if (! cancelExpr().isEmpty()) {
ItemExpr * newCancelExprTree =
cancelExpr().rebuildExprTree(ITM_AND,TRUE,TRUE);
expGen->generateExpr(newCancelExprTree->getValueId(), ex_expr::exp_SCAN_PRED,
&cancelExpression);
}
//
// For overflow
//
// ( The following are meaningless if ! unlimitedHistoryRows() )
NABoolean noOverflow =
CmpCommon::getDefault(EXE_BMO_DISABLE_OVERFLOW) == DF_ON ;
NABoolean logDiagnostics =
CmpCommon::getDefault(EXE_DIAGNOSTIC_EVENTS) == DF_ON ;
NABoolean possibleMultipleCalls = generator->getRightSideOfFlow() ;
short scratchTresholdPct =
(short) CmpCommon::getDefaultLong(SCRATCH_FREESPACE_THRESHOLD_PERCENT);
// determione the memory usage (amount of memory as percentage from total
// physical memory used to initialize data structures)
unsigned short memUsagePercent =
(unsigned short) getDefault(BMO_MEMORY_USAGE_PERCENT);
short memPressurePct = (short)getDefault(GEN_MEM_PRESSURE_THRESHOLD);
historyRecLen = ROUND8(historyRecLen);
Lng32 maxNumberOfOLAPBuffers;
Lng32 maxRowsInOLAPBuffer;
Lng32 minNumberOfOLAPBuffers;
Lng32 numberOfWinOLAPBuffers;
Lng32 olapBufferSize;
computeHistoryParams(historyRecLen,
maxRowsInOLAPBuffer,
minNumberOfOLAPBuffers,
numberOfWinOLAPBuffers,
maxNumberOfOLAPBuffers,
olapBufferSize);
ComTdbSequence *sequenceTdb
= new(space) ComTdbSequence(readSeqExpr,
returnExpr,
postPred,
cancelExpression,
getMinFollowingRows(),
#pragma nowarn(1506) // warning elimination
historyRecLen,
historyAtpIndex,
childTdb,
givenCriDesc,
returnCriDesc,
(queue_index)getDefault(GEN_SEQFUNC_SIZE_DOWN),
(queue_index)getDefault(GEN_SEQFUNC_SIZE_UP),
getDefault(GEN_SEQFUNC_NUM_BUFFERS),
getDefault(GEN_SEQFUNC_BUFFER_SIZE),
olapBufferSize,
maxNumberOfOLAPBuffers,
numHistoryRows(),
getUnboundedFollowing(),
logDiagnostics,
possibleMultipleCalls,
scratchTresholdPct,
memUsagePercent,
memPressurePct,
maxRowsInOLAPBuffer,
minNumberOfOLAPBuffers,
numberOfWinOLAPBuffers,
noOverflow,
checkPartChangeExpr);
#pragma warn(1506) // warning elimination
generator->initTdbFields(sequenceTdb);
// update the estimated value of HistoryRowLength with actual value
//setEstHistoryRowLength(historyIds.getRowLength());
double sequenceMemEst = getEstimatedRunTimeMemoryUsage(sequenceTdb);
generator->addToTotalEstimatedMemory(sequenceMemEst);
if(!generator->explainDisabled()) {
Lng32 seqMemEstInKBPerCPU = (Lng32)(sequenceMemEst / 1024) ;
seqMemEstInKBPerCPU = seqMemEstInKBPerCPU/
(MAXOF(generator->compilerStatsInfo().dop(),1));
generator->setOperEstimatedMemory(seqMemEstInKBPerCPU);
generator->
setExplainTuple(addExplainInfo(sequenceTdb,
childExplainTuple,
0,
generator));
generator->setOperEstimatedMemory(0);
}
sequenceTdb->setScratchIOVectorSize((Int16)getDefault(SCRATCH_IO_VECTOR_SIZE_HASH));
sequenceTdb->setOverflowMode(generator->getOverflowMode());
sequenceTdb->setBmoMinMemBeforePressureCheck((Int16)getDefault(EXE_BMO_MIN_SIZE_BEFORE_PRESSURE_CHECK_IN_MB));
if(generator->getOverflowMode() == ComTdb::OFM_SSD )
sequenceTdb->setBMOMaxMemThresholdMB((UInt16)(ActiveSchemaDB()->
getDefaults()).
getAsLong(SSD_BMO_MAX_MEM_THRESHOLD_IN_MB));
else
sequenceTdb->setBMOMaxMemThresholdMB((UInt16)(ActiveSchemaDB()->
getDefaults()).
getAsLong(EXE_MEMORY_AVAILABLE_IN_MB));
// The CQD EXE_MEM_LIMIT_PER_BMO_IN_MB has precedence over the mem quota sys
NADefaults &defs = ActiveSchemaDB()->getDefaults();
UInt16 mmu = (UInt16)(defs.getAsDouble(EXE_MEM_LIMIT_PER_BMO_IN_MB));
UInt16 numBMOsInFrag = (UInt16)generator->getFragmentDir()->getNumBMOs();
if (mmu != 0)
sequenceTdb->setMemoryQuotaMB(mmu);
else {
// Apply quota system if either one the following two is true:
// 1. the memory limit feature is turned off and more than one BMOs
// 2. the memory limit feature is turned on
NABoolean mlimitPerCPU = defs.getAsDouble(EXE_MEMORY_LIMIT_PER_CPU) > 0;
if ( mlimitPerCPU || numBMOsInFrag > 1 ) {
double memQuota =
computeMemoryQuota(generator->getEspLevel() == 0,
mlimitPerCPU,
generator->getBMOsMemoryLimitPerCPU().value(),
generator->getTotalNumBMOsPerCPU(),
generator->getTotalBMOsMemoryPerCPU().value(),
numBMOsInFrag,
generator->getFragmentDir()->getBMOsMemoryUsage()
);
sequenceTdb->setMemoryQuotaMB( UInt16(memQuota) );
}
}
generator->setCriDesc(givenCriDesc, Generator::DOWN);
generator->setCriDesc(returnCriDesc, Generator::UP);
generator->setGenObj(this, sequenceTdb);
return 0;
}
// PhysSequence::preCodeGen() -------------------------------------------
// Perform local query rewrites such as for the creation and
// population of intermediate tables, for accessing partitioned
// data. Rewrite the value expressions after minimizing the dataflow
// using the transitive closure of equality predicates.
//
// PhysSequence::preCodeGen() - is basically the same as the RelExpr::
// preCodeGen() except that here we replace the VEG references in the
// sortKey() list, as well as the selectionPred().
//
// Parameters:
//
// Generator *generator
// IN/OUT : A pointer to the generator object which contains the state,
// and tools (e.g. expression generator) to generate code for
// this node.
//
// ValueIdSet &externalInputs
// IN : The set of external Inputs available to this node.
//
//
RelExpr * PhysSequence::preCodeGen(Generator * generator,
const ValueIdSet & externalInputs,
ValueIdSet &pulledNewInputs)
{
if (nodeIsPreCodeGenned())
return this;
// Resolve the VEGReferences and VEGPredicates, if any, that appear
// in the Characteristic Inputs, in terms of the externalInputs.
//
getGroupAttr()->resolveCharacteristicInputs(externalInputs);
// My Characteristic Inputs become the external inputs for my children.
//
ValueIdSet childPulledInputs;
child(0) = child(0)->preCodeGen(generator, externalInputs, pulledNewInputs);
if (! child(0).getPtr())
return NULL;
// process additional input value ids the child wants
getGroupAttr()->addCharacteristicInputs(childPulledInputs);
pulledNewInputs += childPulledInputs;
// The VEG expressions in the selection predicates and the characteristic
// outputs can reference any expression that is either a potential output
// or a characteristic input for this RelExpr. Supply these values for
// rewriting the VEG expressions.
//
ValueIdSet availableValues;
getInputValuesFromParentAndChildren(availableValues);
// The sequenceFunctions() have access to only the Input
// Values. These can come from the parent or be the outputs of the
// child.
//
sequenceFunctions().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
sequencedColumns().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
requiredOrder().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
cancelExpr().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
partition().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
//checkPartitionChangeExpr().
// replaceVEGExpressions(availableValues,
// getGroupAttr()->getCharacteristicInputs());
// The selectionPred has access to only the output values generated by
// Sequence and input values from the parent.
//
getInputAndPotentialOutputValues(availableValues);
// Rewrite the selection predicates.
//
NABoolean replicatePredicates = TRUE;
selectionPred().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs(),
FALSE, // no key predicates here
0 /* no need for idempotence here */,
replicatePredicates
);
// Replace VEG references in the outputs and remove redundant
// outputs.
//
getGroupAttr()->resolveCharacteristicOutputs
(availableValues,
getGroupAttr()->getCharacteristicInputs());
addCancelExpr(generator->wHeap());
///addCheckPartitionChangeExpr(generator->wHeap());
transformOlapFunctions(generator->wHeap());
if ( getUnboundedFollowing() ) {
// Count this Seq as a BMO and add its needed memory to the total needed
generator->incrNumBMOs();
if ((ActiveSchemaDB()->getDefaults()).
getAsDouble(EXE_MEMORY_LIMIT_PER_CPU) > 0)
generator->incrBMOsMemory(getEstimatedRunTimeMemoryUsage(TRUE));
}
else
generator->incrNBMOsMemoryPerCPU(getEstimatedRunTimeMemoryUsage(TRUE));
markAsPreCodeGenned();
return this;
} // PhysSequence::preCodeGen
// PhysSample::preCodeGen() -------------------------------------------
// Perform local query rewrites such as for the creation and
// population of intermediate tables, for accessing partitioned
// data. Rewrite the value expressions after minimizing the dataflow
// using the transitive closure of equality predicates.
//
// PhysSample::preCodeGen() - is basically the same as the RelExpr::
// preCodeGen() except that here we replace the VEG references in the
// sortKey() list, as well as the selectionPred().
//
// Parameters:
//
// Generator *generator
// IN/OUT : A pointer to the generator object which contains the state,
// and tools (e.g. expression generator) to generate code for
// this node.
//
// ValueIdSet &externalInputs
// IN : The set of external Inputs available to this node.
//
//
RelExpr * PhysSample::preCodeGen(Generator * generator,
const ValueIdSet & externalInputs,
ValueIdSet &pulledNewInputs)
{
// Do nothing if this node has already been processed.
//
if (nodeIsPreCodeGenned())
return this;
// Resolve the VEGReferences and VEGPredicates, if any, that appear
// in the Characteristic Inputs, in terms of the externalInputs.
//
getGroupAttr()->resolveCharacteristicInputs(externalInputs);
// My Characteristics Inputs become the external inputs for my children.
// preCodeGen my only child.
//
ValueIdSet childPulledInputs;
child(0) = child(0)->preCodeGen(generator, externalInputs, pulledNewInputs);
if(!child(0).getPtr())
return NULL;
// Process additional any additional inputs the child wants.
//
getGroupAttr()->addCharacteristicInputs(childPulledInputs);
pulledNewInputs += childPulledInputs;
// The sampledCols() only have access to the Input Values.
// These can come from the parent or be the outputs of the child.
// Compute the set of available values for the sampledCols() and use
// these to resolve any VEG references that the sampledCols() may need.
//
ValueIdSet availableValues;
getInputValuesFromParentAndChildren(availableValues);
sampledColumns().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs());
// Ditto, for the balance expression.
//
balanceExpr().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs());
requiredOrder().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
// The selectionPred has access to only the output values generated by
// Sequence and input values from the parent. Compute the set of available
// values for the selectionPred and resolve any VEG references
// that the selection predicates may need.
//
getInputAndPotentialOutputValues(availableValues);
NABoolean replicatePredicates = TRUE;
selectionPred().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs(),
FALSE, // no key predicates here
0 /* no need for idempotence here */,
replicatePredicates
);
// Resolve VEG references in the outputs and remove redundant
// outputs.
//
getGroupAttr()->resolveCharacteristicOutputs
(availableValues,
getGroupAttr()->getCharacteristicInputs());
// Mark this node as done and return.
//
markAsPreCodeGenned();
return this;
} // PhysSample::preCodeGen
short
PhysSample::codeGen(Generator *generator)
{
// Get a local handle on some of the generator objects.
//
CollHeap *wHeap = generator->wHeap();
Space *space = generator->getSpace();
MapTable *mapTable = generator->getMapTable();
ExpGenerator *expGen = generator->getExpGenerator();
// Allocate a new map table for this node. This must be done
// before generating the code for my child so that this local
// map table will be sandwiched between the map tables already
// generated and the map tables generated by my offspring.
//
// Only the items available as output from this node will
// be put in the local map table. Before exiting this function, all of
// my offsprings map tables will be removed. Thus, none of the outputs
// from nodes below this node will be visible to nodes above it except
// those placed in the local map table and those that already exist in
// my ancestors map tables. This is the standard mechanism used in the
// generator for managing the access to item expressions.
//
MapTable *localMapTable = generator->appendAtEnd();
// Since this operation doesn't modify the row on the way down the tree,
// go ahead and generate the child subtree. Capture the given composite row
// descriptor and the child's returned TDB and composite row descriptor.
//
ex_cri_desc * givenCriDesc = generator->getCriDesc(Generator::DOWN);
child(0)->codeGen(generator);
ComTdb *childTdb = (ComTdb*)generator->getGenObj();
ex_cri_desc * childCriDesc = generator->getCriDesc(Generator::UP);
ExplainTuple *childExplainTuple = generator->getExplainTuple();
// Geneate the sampling expression.
//
ex_expr *balExpr = NULL;
Int32 returnFactorOffset = 0;
ValueId val;
val = balanceExpr().init();
if(balanceExpr().next(val))
expGen->generateSamplingExpr(val, &balExpr, returnFactorOffset);
// Alias the sampleColumns() so that they reference the underlying
// expressions directly. This is done to avoid having to generate and
// execute a project expression that simply moves the columns from
// one tupp to another to reflect the application of the sampledCol
// function.
//
// ValueId valId;
// for(valId = sampledColumns().init();
// sampledColumns().next(valId);
// sampledColumns().advance(valId))
// {
// MapInfo *mapInfoChild = localMapTable->getMapInfoAsIs
// (valId.getItemExpr()->child(0)->castToItemExpr()->getValueId());
// GenAssert(mapInfoChild, "Sample::codeGen -- no child map info.");
// Attributes *attr = mapInfoChild->getAttr();
// MapInfo *mapInfo = localMapTable->addMapInfoToThis(valId, attr);
// mapInfo->codeGenerated();
// }
// check if any of the columns inthe sampled columns are lob columns. If so, return an error.
ValueId valId;
for(valId = sampledColumns().init();
sampledColumns().next(valId);
sampledColumns().advance(valId))
{
const NAType &colType = valId.getType();
if ((colType.getFSDatatype() == REC_BLOB) ||
(colType.getFSDatatype() == REC_CLOB))
{
*CmpCommon::diags() << DgSqlCode(-4322);
GenExit();
}
}
// Now, remove all attributes from the map table except the
// the stuff in the local map table -- the result of this node.
//
// localMapTable->removeAll();
// Generate the expression to evaluate predicate on the sampled row.
//
ex_expr *postPred = 0;
if (!selectionPred().isEmpty()) {
ItemExpr * newPredTree
= selectionPred().rebuildExprTree(ITM_AND,TRUE,TRUE);
expGen->generateExpr(newPredTree->getValueId(), ex_expr::exp_SCAN_PRED,
&postPred);
}
// Construct the Sample TDB.
//
ComTdbSample *sampleTdb
= new(space) ComTdbSample(NULL,
balExpr,
returnFactorOffset,
postPred,
childTdb,
givenCriDesc,
childCriDesc,
(queue_index)getDefault(GEN_SAMPLE_SIZE_DOWN),
(queue_index)getDefault(GEN_SAMPLE_SIZE_UP));
generator->initTdbFields(sampleTdb);
if(!generator->explainDisabled()) {
generator->
setExplainTuple(addExplainInfo(sampleTdb,
childExplainTuple,
0,
generator));
}
generator->setCriDesc(givenCriDesc, Generator::DOWN);
generator->setCriDesc(childCriDesc, Generator::UP);
generator->setGenObj(this, sampleTdb);
return 0;
}
