// ***************************************************************************
// Initialize the several hash tables that map output list elements:
// outputByIDHash_ - Using the ID of the output item as the key.
// outputByColumnName_ - Using the "ID Qualified" column name as the key.
// outputByExprText_ - Using the expression text as the key.
// outputByInputColumns_ - Using the name of expression input column as the key.
// ***************************************************************************
void MVDetails::initOutputs(const QRJBBPtr jbb, CollHeap* heap)
{
// Match the output elements with their names.
const QROutputListPtr outputList = jbb->getOutputList();
assertLogAndThrow(CAT_MATCHTST_MVDETAILS, LL_MVQR_FAIL,
outputList != NULL, QRLogicException,
"Output list is null.");
// For each output list element
for (CollIndex i=0; i<outputList->entries(); i++)
{
QROutputPtr output = (*outputList)[i];
// Set the ordinal number of the output element.
output->setColPos(i+1);
// Get the output item (column or expression).
QRElementPtr outputItem = output->getOutputItem()->getReferencedElement();
const NAString& id = outputItem->getID();
// Insert the ID of the output item (whatever it is) into the ID hash.
outputByIDHash_.insert(&id, output);
// OK, now lets check what type of output item it is.
switch (outputItem->getElementType())
{
case ET_Column:
{
// If its an output column, add it to the output column by name hash.
const QRColumnPtr col = outputItem->downCastToQRColumn();
const QRElementPtr tableElem = getElementForID(col->getTableID());
NABoolean hasLOJParent = tableElem->downCastToQRTable()->hasLOJParent();
if (!isFromJoin(col) || hasLOJParent)
{
// Compute the "ID Qualified" column name as the key.
const NAString* idQualifiedColName =
calcIDQualifiedColumnName(col->getTableID(), col->getColumnName(), heap);
// Insert into the hash table.
outputByColumnName_.insert(idQualifiedColName, output);
}
else
{
// If its an equality set, insert all the participating columns
// as pointing to the same MV output column.
const QRJoinPredPtr jp = getJoinPred(col);
const QRJoinPredPtr joinPredElement = jp->downCastToQRJoinPred();
addEqualitySet(joinPredElement, FALSE, output, heap);
}
break;
}
case ET_JoinPred:
{
assertLogAndThrow(CAT_MATCHTST_MVDETAILS, LL_MVQR_FAIL,
(outputItem->getElementType() == ET_JoinPred), QRLogicException,
"Unexpected JoinPred element.");
// If its an equality set, insert all the participating columns
// as pointing to the same MV output column.
const QRJoinPredPtr joinPredElement = outputItem->downCastToQRJoinPred();
addEqualitySet(joinPredElement, FALSE, output, heap);
break;
}
case ET_Expr:
{
// This is an expression. Insert the expression text into the expression hash.
const QRExprPtr expr = outputItem->downCastToQRExpr();
const NAString& exprText = expr->getExprText();
outputByExprText_.insert(&exprText, output);
QRLogger::log(CAT_MATCHTST_MVDETAILS, LL_DEBUG,
"Adding output expression: %s.", exprText.data());
// Also map the expressions's input columns to it.
// This call to getInitColumns() also inits the input list using the
// right heap.
const ElementPtrList& inputs = expr->getInputColumns(heap);
if (inputs.entries() > 0)
{
for (CollIndex j=0; j<inputs.entries(); j++)
{
QRElementPtr inputElem = inputs[j]->getReferencedElement();
if (inputElem->getElementType() == ET_Column)
{
QRColumnPtr inputCol = inputElem->downCastToQRColumn();
// Compute the "ID Qualified" column name as the key.
const NAString* idQualifiedColName =
calcIDQualifiedColumnName(inputCol->getTableID(), inputCol->getColumnName(), heap);
outputByInputColumns_.insert(idQualifiedColName, output);
}
else
{
QRJoinPredPtr inputJoinPred = inputElem->downCastToQRJoinPred();
addEqualitySet(inputJoinPred, TRUE, output, heap);
}
}
}
// Check if this is the COUNT(*) function.
QRExplicitExprPtr rootExpr = expr->getExprRoot();
if (rootExpr->getElementType() == ET_Function)
{
QRFunctionPtr func = rootExpr->downCastToQRFunction();
if (func->getAggregateFunc() == QRFunction::AFT_COUNTSTAR)
{
// Found it, now remember it for later use.
// If a COUNT(*) equivalent function has already been found
// (see below) - overwrite it.
countStar_ = output;
}
else if (countStar_ == NULL &&
func->isCountStarEquivalent(heap) )
{
// Well, we didn't find a COUNT(*) yet, but we found a COUNT(a)
// and the input column is NOT NOLL, we can use it as a COUNT(*) column.
countStar_ = output;
}
}
} // end of case ET_Expr
break;
} // switch on element type
} // for on output list elements
} // MVDetails::initOutputs()
// ***************************************************************************
// ***************************************************************************
void JBBDetails::initRangePreds(CollHeap* heap)
{
// Initialize the Range predicates.
const QRRangePredListPtr rangePreds = jbbDesc_->getHub()->getRangePredList();
if (rangePreds==NULL || rangePreds->entries() == 0)
{
hasNoRangePredicates_ = TRUE;
return;
}
for (CollIndex k=0; k<rangePreds->entries(); k++)
{
const QRRangePredPtr rangePred = (*rangePreds)[k];
const QRElementPtr rangeElem = rangePred->getRangeItem()->getReferencedElement();
if (rangeElem->getElementType() == ET_Column && rangePred->isSingleValue())
{
constColumns_.insert(&rangeElem->getID());
}
// For query descriptors, only check for const columns.
if (!isAnMV_)
continue;
if (rangeElem->getElementType() == ET_Column)
{
const QRColumnPtr rangeColumn = rangeElem->downCastToQRColumn();
if (!descDetails_->isFromJoin(rangeColumn))
{
// This column is NOT part of a join predicate.
BaseTableDetailsPtr rangeTable = getBaseTableByID(rangeColumn->getTableID());
rangeTable->addRangePredicateOnColumn(rangePred, rangeColumn);
}
else
{
// This column IS part of a join predicate.
// Insert the range pred for all the participating columns.
const QRJoinPredPtr jp = descDetails_->getJoinPred(rangeColumn);
const ElementPtrList& equalitySet = jp->getEqualityList();
for (CollIndex i=0; i<equalitySet.entries(); i++)
{
const QRElementPtr halfPred = equalitySet[i];
// Now lets look at the equality set members
// Ignore members that are not simple columns.
if (halfPred->getElementType() != ET_Column)
continue;
const QRColumnPtr eqSetColumn = halfPred->getReferencedElement()->downCastToQRColumn();
BaseTableDetailsPtr rangeTable = getBaseTableByID(eqSetColumn->getTableID());
rangeTable->addRangePredicateOnColumn(rangePred, eqSetColumn);
}
}
}
else if (rangeElem->getElementType() == ET_JoinPred)
{
assertLogAndThrow(CAT_MATCHTST_MVDETAILS, LL_MVQR_FAIL,
(rangeElem->getElementType() == ET_JoinPred), QRLogicException,
"Unexpected JoinPred element.");
// If its an equality set, insert the range pred for all the participating columns.
const QRJoinPredPtr joinPredElement = rangeElem->downCastToQRJoinPred();
const ElementPtrList& equalitySet = joinPredElement->getEqualityList();
for (CollIndex i=0; i<equalitySet.entries(); i++)
{
const QRElementPtr halfPred = equalitySet[i];
// Now lets look at the equality set members
// Ignore members that are not simple columns.
if (halfPred->getElementType() != ET_Column)
continue;
const QRColumnPtr eqSetColumn = halfPred->getReferencedElement()->downCastToQRColumn();
BaseTableDetailsPtr rangeTable = getBaseTableByID(eqSetColumn->getTableID());
rangeTable->addRangePredicateOnColumn(rangePred, eqSetColumn);
}
}
else
{
// The range pred is on an expression. Insert it for all the expression's input columns.
const QRExprPtr rangeExpr = rangeElem->downCastToQRExpr();
if (rangeExpr->getExprRoot()->containsAnAggregate(heap))
{
hasHavingPredicates_ = TRUE;
}
// Verify we have a single input column
// No input columns mean its a COUNT(*), which is OK too.
const ElementPtrList& inputs = rangeExpr->getInputColumns(heap);
assertLogAndThrow(CAT_MATCHTST_MVDETAILS, LL_MVQR_FAIL,
(inputs.entries() <= 1), QRLogicException,
"Range predicate expression must have a single input at most.");
const NAString& predText = rangeExpr->getExprText();
// Look it up in the hash table: do we already have a range pred with this text?
RangePredPtrList* predList = getRangePredsOnExpression(predText);
if (predList == NULL)
{
// No, its the first one. Create a new list.
predList = new(heap) RangePredPtrList(heap);
// And insert it into the hash table.
rangePredicates_.insert(&predText, predList);
}
// Insert the predicate into the pred list.
predList->insert(rangePred);
}
}
} // JBBDetails::init()
