// LCOV_EXCL_START
// Used for other RelExpr but not MultiJoin
void MultiJoin::synthEstLogProp(const EstLogPropSharedPtr& inputEstLogProp)
{
CMPASSERT(inputEstLogProp->getNodeSet());
Join * preferredJoin = jbbSubset_.getPreferredJoin();
CMPASSERT(preferredJoin->isJoinFromMJSynthLogProp());
EstLogPropSharedPtr myEstLogProp =
preferredJoin->getGroupAttr()->outputLogProp(inputEstLogProp);
getGroupAttr()->addInputOutputLogProp (inputEstLogProp, myEstLogProp, NULL);
} // MultiJoin::synthEstLogProp
EstLogPropSharedPtr AppliedStatMan::synthesizeLogProp(
const CANodeIdSet * nodeSet,
EstLogPropSharedPtr &inLP)
{
EstLogPropSharedPtr outputEstLogProp;
CANodeIdSet combinedNodeSetWithInput = *nodeSet;
if (inLP->isCacheable())
{
CANodeIdSet * inNodeSet = inLP->getNodeSet();
// if inLP are cacheable these should have a nodeSet attached
// if not, assert in debug mode. In release mode, set the properties
// as not cacheable. These will then be looked into group attr cache
if (inNodeSet == NULL)
{
CCMPASSERT(inNodeSet != NULL);
inLP->setCacheableFlag(FALSE);
}
else
{
// check ASM cache for the estLogProps of nodeSet for the given
// inLP
combinedNodeSetWithInput.insert(*inNodeSet);
if ((outputEstLogProp =\
getCachedStatistics(&combinedNodeSetWithInput)) != NULL)
return outputEstLogProp;
}
}
if(nodeSet->entries() == 1)
return getStatsForCANodeId(nodeSet->getFirst(), inLP);
JBBSubset * jbbSubset = nodeSet->jbbcsToJBBSubset();
Join * preferredJoin = jbbSubset->getPreferredJoin();
//CMPASSERT(preferredJoin->isJoinFromMJSynthLogProp());
outputEstLogProp = preferredJoin->getGroupAttr()->outputLogProp(inLP);
return outputEstLogProp;
} // AppliedStatMan::synthesizeLogProp
// get Stats after applying given join predicates on the JBBC
EstLogPropSharedPtr AppliedStatMan::getStatsForGivenJoinPredsOnJBBC(
const CANodeIdSet jbbSubset,
CANodeId jbbc,
const ValueIdSet joinPreds,
const ValueIdSet localPreds,
EstLogPropSharedPtr &inLP)
{
EstLogPropSharedPtr inputLP = inLP;
if(inputLP == (*GLOBAL_EMPTY_INPUT_LOGPROP))
inputLP = jbbc.getJBBInput();
EstLogPropSharedPtr outputEstLogProp;
// form a Join expression with the given join predicates, and compute
// output estimated logical properties. These properties should not be cached
// in the ASM cache, hence set the "cacheable" flag to FALSE in inLP.
// We do not want to modify the "cacheable" flag in the inLP, hence make a
// copy of these logical properties.
EstLogPropSharedPtr nonCacheableInLP(new (HISTHEAP) EstLogProp (*inputLP));
nonCacheableInLP->setCacheableFlag(FALSE);
Join * joinExpr = formJoinExprForJoinOnJBBC(jbbSubset,
jbbc,
&localPreds,
&joinPreds,
nonCacheableInLP,
FALSE);
// synthesize estimate logical properties for the join
outputEstLogProp = joinExpr->getGroupAttr()->outputLogProp(nonCacheableInLP);
return outputEstLogProp;
} // AppliedStatMan::getStatsForGivenJoinPreds
Join* MultiJoin::splitSubset(const JBBSubset & leftSet,
const JBBSubset & rightSet,
NABoolean reUseMJ) const
{
// At this point assert that none of the subsets has a group by member
CMPASSERT ( (jbbSubset_.getGB() == NULL_CA_ID) &&
(leftSet.getGB() == NULL_CA_ID) &&
(rightSet.getGB() == NULL_CA_ID) );
#ifndef NDEBUG
// assert that left + right == subSet_
// and left intersect right = phi
CANodeIdSet unionSet(leftSet.getJBBCs());
CANodeIdSet intersectSet(leftSet.getJBBCs());
unionSet += rightSet.getJBBCs();
intersectSet.intersectSet(rightSet.getJBBCs());
CMPASSERT ( (unionSet == jbbSubset_.getJBBCs()) &&
(intersectSet.entries() == 0 ));
#endif
// Note: Joins including left, semi, anti semi are only created when
// a single jbbc connected via one of them is split as a single right
// child. InnerNonSemi joins can be created for any split i.e. any
// number of jbbcs on the left and the right of the join, but special
// joins (i.e. left, semi and anti semi joins) are only created when
// there is a single right child i.e. the rightSet contains only one
// jbbc that is connected via a special join. This is enforced as follows
//
// * The leftSet should be legal: This means that for every jbbc in the
// leftSet any predecessor jbbcs should be present in the leftSet.
// * The rightSet is either a single jbbc or if the rightSet has more
// than one jbbc then it should be legal, note that a jbbc connected
// via a special join is not a legal set by itself but we allow
// creation of special joins assuming the predecessors are present
// in the leftSet.
//
// An implicit assumption here is that 'this' MultiJoin is legal, which
// is fair since apart from the top level multijoin, rest of the multijoins
// are produced by splitting the top level multijoin. This method should
// not produce illegal multijoins, since we check both leftSet and rightSet
// for legality. Only time we don't check for legality is when the rightChild
// is a single jbbc, and a single jbbc does not result in a multijoin.
if(!leftSet.legal())
return NULL;
if((rightSet.getJBBCs().entries() > 1) && (!rightSet.legal()))
return NULL;
// everything here goes to statement heap
CollHeap* outHeap = CmpCommon::statementHeap();
RelExpr* child0 = generateSubsetExpr(leftSet, reUseMJ);
RelExpr* child1 = generateSubsetExpr(rightSet, reUseMJ);
// Flag to remember to pass on the derivedFromRoutineJoin flag if needed.
NABoolean derivedFromRoutineJoin(FALSE);
// now form a JoinExpr with these left and right children.
Join * result = NULL;
// if the rightSet is a single jbbc, then it could be connected via
// a special join. In such a case we have to create the appropriate
// join operator
if(rightSet.getJBBCs().entries() == 1){
JBBC * rightChild = rightSet.getJBBCs().getFirst().getNodeAnalysis()
->getJBBC();
Join * rightChildParentJoin = rightChild->getOriginalParentJoin();
// If rightChildParentJoin is NULL, then the child is the left
// child of the left most join and is considered to be connected
// via a InnerNonSemi join.
if(rightChildParentJoin)
{
if(rightChildParentJoin->derivedFromRoutineJoin())
derivedFromRoutineJoin = TRUE;
if(rightChildParentJoin->isSemiJoin())
result = new (outHeap) Join(child0, child1, REL_SEMIJOIN, NULL);
if(rightChildParentJoin->isAntiSemiJoin())
result = new (outHeap) Join(child0, child1, REL_ANTI_SEMIJOIN, NULL);
if(rightChildParentJoin->isLeftJoin())
{
// left joins can have filter preds, i.e. predicates that
// are applied as filters after applying the join predicate.
// We need to set them here.
result = new (outHeap) Join(child0, child1, REL_LEFT_JOIN, NULL);
result->setSelectionPredicates(rightChild->getLeftJoinFilterPreds());
}
if(rightChildParentJoin->isRoutineJoin())
{
derivedFromRoutineJoin = TRUE;
result = new (outHeap) Join(child0, child1, REL_ROUTINE_JOIN, NULL);
ValueIdSet routineJoinFilterPreds = rightChild->getRoutineJoinFilterPreds();
ValueIdSet predsToAddToRoutineJoin;
// add covered filter preds
for (ValueId filterPred= routineJoinFilterPreds.init();
routineJoinFilterPreds.next(filterPred);
routineJoinFilterPreds.advance(filterPred) )
{
if(jbbSubset_.coversExpr(filterPred))
predsToAddToRoutineJoin += filterPred;
}
result->setSelectionPredicates(predsToAddToRoutineJoin);
}
if(result)
{
// set the join predicate for special joins, note predicates
// for regular InnerNonSemi joins are set as selection predicates
// in the join relexpr.
result->setJoinPred(rightChild->getPredsWithPredecessors());
result->nullInstantiatedOutput().insert(rightChild->
nullInstantiatedOutput());
}
}
}
// The join to be created is a regular InnerNonSemi join
if (!result)
result = new (outHeap) Join(child0, child1, REL_JOIN, NULL);
// Make sure we carry the derivedFromRoutineJoin flag with us
if (derivedFromRoutineJoin)
result->setDerivedFromRoutineJoin();
// Share my groupAttr with result
result->setGroupAttr(getGroupAttr());
// get inner join predicates
ValueIdSet selPreds = rightSet.joinPredsWithOther(leftSet);
// get left join filter preds if any
selPreds += result->getSelectionPredicates();
result->setSelectionPredicates(selPreds);
result->findEquiJoinPredicates();
// May be I could save a little if i pushdown only to the child(ren)
// that are not already JBBCs, i.e. multijoins
result->pushdownCoveredExpr
(result->getGroupAttr()->getCharacteristicOutputs(),
result->getGroupAttr()->getCharacteristicInputs(),
result->selectionPred());
// We used CutOp as children, to avoid pushing predicates to JBBCs.
// Now put the actual expression back in case the child is a JBBCs
if(leftSet.getJBBCs().entries() == 1)
result->setChild(0, getJBBCRelExpr(leftSet.getJBBCs().getFirst()));
// We used CutOp as children, to avoid pushing predicates to JBBCs.
// Now put the actual expression back in case the child is a JBBCs
if(rightSet.getJBBCs().entries() == 1)
result->setChild(1, getJBBCRelExpr(rightSet.getJBBCs().getFirst()));
// Temp fixup. We need to take the selectionPred out of MultiJoin
// for now to prevent that pushed expr from being there. selectionPred
// is not being used now in MultiJoin xxx.
if (leftSet.getJBBCs().entries() > 1)
result->child(0)->selectionPred().clear();
if (rightSet.getJBBCs().entries() > 1)
result->child(1)->selectionPred().clear();
return result;
}
// LCOV_EXCL_START :cnu
EstLogPropSharedPtr AppliedStatMan::joinEstLogProps (
const EstLogPropSharedPtr& leftEstLogProp,
const EstLogPropSharedPtr& rightEstLogProp,
const EstLogPropSharedPtr& inLP)
{
EstLogPropSharedPtr outputEstLogProp;
NABoolean cacheable = FALSE;
CANodeIdSet * inputNodeSet = inLP->getNodeSet();
// These nodesets could be NULL, if the estLogProps to which they
// belong are not cacheable
CANodeIdSet * leftNodeSet = leftEstLogProp->getNodeSet();
CANodeIdSet * rightNodeSet = rightEstLogProp->getNodeSet();
if ((leftEstLogProp->isCacheable()) &&
(rightEstLogProp->isCacheable()) &&
(inLP->isCacheable()) )
{
CCMPASSERT(leftNodeSet != NULL);
CCMPASSERT(rightNodeSet != NULL);
CCMPASSERT(inputNodeSet != NULL);
if (leftNodeSet && rightNodeSet && inputNodeSet)
{
cacheable = TRUE;
}
}
if (cacheable)
{
// check the ASM cache to see if outputEstLogProp for these
// NodeSets appear for the given inputEstLogProp
CANodeIdSet combineNodeSet = *leftNodeSet;
combineNodeSet.insert(*rightNodeSet);
CANodeIdSet combinedWithInputNodeSet = combineNodeSet;
combinedWithInputNodeSet.insert(*inputNodeSet);
outputEstLogProp = getCachedStatistics(&combinedWithInputNodeSet);
if (outputEstLogProp != NULL)
return outputEstLogProp;
}
JBBSubset * newJBBSubset = NULL;
ValueIdSet setOfPredicates;
if (leftNodeSet && rightNodeSet)
{
// join predicates can be obtained from EstLogProp, only
// if these corresponded to complete set of predicates -
// all local or complete join. Also, we need a
// combinedJBBSubset to set in the fake join expression
// that we will be creating.
newJBBSubset = leftNodeSet->computeJBBSubset();
JBBSubset rightJBBSubset = *(rightNodeSet->computeJBBSubset());
setOfPredicates = newJBBSubset->joinPredsWithOther(rightJBBSubset);
// Since the properties from this group are cacheable, hence the
// group attributes for the new join expression should contain
// the combined JBBsubset of the left and the right children
newJBBSubset->addSubset(rightJBBSubset);
}
// inputEstLogProp would be either empty input estLogProp or from the
// outer child. If cacheable is TRUE, then newJBBsubset should
// contain the combined left and the right JBB subset. But if
// cacheable is FALSE, newJBBsubset should be NULL
Join * joinExpr = formJoinExprWithEstLogProps(
leftEstLogProp,
rightEstLogProp,
inLP,
&setOfPredicates,
cacheable,
newJBBSubset);
// Now do the actual synthesis and cache statistics in the cache
outputEstLogProp = joinExpr->getGroupAttr()->outputLogProp(inLP);
return outputEstLogProp;
}