// ***************************************************************************
// ***************************************************************************
void MVDetails::addEqualitySet(QRJoinPredPtr joinPredElement,
NABoolean isFromExpr,
QROutputPtr output,
CollHeap* heap)
{
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();
// If this JoinPred element is a column of an LOJ table,
// skip it because it is not really equal to the others.
const QRElementPtr tableElem = getElementForID(eqSetColumn->getTableID());
if (tableElem->downCastToQRTable()->hasLOJParent())
continue;
// Compute the "ID Qualified" column name as the key.
const NAString* idQualifiedColName =
calcIDQualifiedColumnName(eqSetColumn->getTableID(), eqSetColumn->getColumnName(), heap);
// Insert into the hash table.
if (isFromExpr)
outputByInputColumns_.insert(idQualifiedColName, output);
else
outputByColumnName_.insert(idQualifiedColName, output);
}
} // MVDetails::addEqualitySet
// ***************************************************************************
// 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()
LatticeIndexablePtr QRGroupLattice::elementToKey(const QRElementPtr element,
QRJoinSubGraphMapPtr map,
DescriptorDetailsPtr queryDetails,
NABoolean insertMode,
NABoolean isRecursive)
{
QRElementPtr elem = element->getReferencedElement();
QRColumnPtr col = NULL;
if (elem->getElementType() == ET_Column)
{
col = elem->downCastToQRColumn();
if (queryDetails->isFromJoin(col) && !isRecursive)
{
// This groupby element is a join pred.
// During insert, this loop inserts the first column.
// During search, try each equality set element until we find one that
// appears in our array.
const QRJoinPredPtr eqSet = queryDetails->getJoinPred(col);
const ElementPtrList& equalityList = eqSet->getEqualityList();
if (insertMode)
{
// Insert mode - pick the first column of the equality set.
col = equalityList[0]->downCastToQRColumn();
}
else
{
// Search mode - pick the first equality set entry that is found in this LatticeIndex.
for (CollIndex i=0; i<equalityList.entries(); i++)
{
QRElementPtr entry = equalityList[i]->getReferencedElement();
// Call recursively for each join pred column.
LatticeIndexablePtr entryKey = elementToKey(entry, map, queryDetails, insertMode, TRUE);
if (entryKey == NULL)
continue;
if (lattice_->contains(entryKey))
{
// Found it in the lattice index.
col = entry->downCastToQRColumn();
break;
}
} // for ( )
// If none of the entries was found - give up now.
if (col == NULL)
return NULL;
} // if insert mode
} // if JoinPred
} // if Column
NAString* key = NULL;
if (col != NULL)
{
col = col->getReferencedElement()->downCastToQRColumn();
const NAString& tableID = col->getTableID();
Int32 Inx = map->getIndexForTable(tableID);
if (Inx == -1)
{
assertLogAndThrow(CAT_GRP_LATTCE_INDX, LL_ERROR,
!insertMode, QRLogicException,
"Table index not found in Insert mode (Inserting a multi-JBB MV?).");
return NULL;
}
char buffer[4096+5];
sprintf(buffer, "%d.%s", Inx, col->getColumnName().data() );
key = new(heap_) NAString(buffer, heap_);
}
else
{
// This is an expression.
// TBD We still do not handle expressions using columns from self-join tables.
key = new(heap_) NAString(element->getSortName(), heap_);
}
// The reverseKeyHash should always use the most recent MV inserted.
if (insertMode)
{
reverseKeyHash_.remove(key);
reverseKeyHash_.insert(key, element);
}
return key;
}