void MVCandidatesForJBBSubset::setSubGraphMap(QRJoinSubGraphMapPtr querySubGraphMap)
{
querySubGraphMap_ = querySubGraphMap;
// Mark that this subGraph is being used for rewrite instructions, so that
// it will not be deleted when the HubIterator is deleted.
querySubGraphMap->getSubGraph()->setStillUsed(TRUE);
}
//*****************************************************************************
//*****************************************************************************
NABoolean MVCandidate::CheckAnExtraHubTable(const NAString* tableID,
QRJoinSubGraphMapPtr mvSubGraphMap,
QRJoinSubGraphMapPtr querySubGraphMap,
NABoolean& extraHubTableWasAdded)
{
QRJoinSubGraphPtr mvSubGraph = mvSubGraphMap->getSubGraph();
QRJoinSubGraphPtr querySubGraph = querySubGraphMap->getSubGraph();
const QRTablePtr queryTableElement =
getQueryDetails()->getElementForID(*tableID)->downCastToQRTable();
const JoinGraphTablePtr queryGraphTable =
querySubGraph->getParentGraph()->getTableByID(queryTableElement->getID());
// If this extra-hub table is not directly connected to the rest of
// the subgraph, skip it for now.
if (queryGraphTable->isConnectedTo(querySubGraph) == FALSE)
{
// Add additional needed extra-hub tables here...
return TRUE;
}
// Find the corresponding MV table
const QRTablePtr mvTableElement = getMvDetails()->getTableFromName(queryTableElement->getTableName());
const JoinGraphTablePtr mvGraphTable =
mvSubGraph->getParentGraph()->getTableByID(mvTableElement->getID());
if (matchPredsFromTableToSubGraph(mvSubGraph,
querySubGraph,
mvGraphTable,
queryGraphTable) == FALSE)
{
// Match failed.
// Release the sandbox subgraphs and disqualify the MVCandidate.
deletePtr(mvSubGraphMap);
deletePtr(querySubGraphMap);
logMVWasDisqualified1("Extra hub table %s is needed but cannot be matched.",
queryTableElement->getTableName().data());
return FALSE;
}
// Add the table to both MV and query subgraphs.
querySubGraph->addTable(queryGraphTable);
mvSubGraph->addTable(mvGraphTable);
// To make sure that Pass 2 matching and result desxcriptor generation will
// work correctly, add the tables to the SubGraphMaps (they will have the same index).
CollIndex index = querySubGraph->entries();
querySubGraphMap->addTable(index, queryGraphTable);
mvSubGraphMap->addTable(index, mvGraphTable);
// We are done with this table, remove it from the list.
extraHubTables_.remove(tableID);
extraHubTableWasAdded = TRUE;
QRLogger::log(CAT_MVCAND, LL_DEBUG,
"ExtraHub table %s was matched for MV %s.",
queryTableElement->getTableName().data(),
mvDetails_->getMVName().data());
return TRUE;
} // MVCandidate::CheckAnExtraHubTable()
NABoolean MVCandidate::CheckExtraHubTables()
{
if (extraHubTables_.entries() == 0)
return TRUE;
// Allocate a new subGraph and subGraphMap for the MV - the one we have is from MVMemo,
// so its considered read-only.
QRJoinSubGraphMapPtr mvSubGraphMap = new(heap_)
QRJoinSubGraphMap(*getMvSubGraphMap(), ADD_MEMCHECK_ARGS(heap_));
// The query subGraph is shared between the MVCandidates that were found
// in the same MVMemo group, so work on a copy.
QRJoinSubGraphMapPtr querySubGraphMap = new(heap_)
QRJoinSubGraphMap(*getJbbSubset()->getQuerySubGraphMap(), ADD_MEMCHECK_ARGS(heap_));
// Loop over the list, each time picking an extra-hub table that is
// directly connected to a table already in the matched sub-graph,
// until all the tables are checked.
do
{
NABoolean extraHubTableWasAdded = FALSE;
// Do the loop backwards because we remove checked extra-hub tables from the list.
for (Int32 i=(CollIndex)extraHubTables_.entries()-1; i>=0; i--)
{
if (CheckAnExtraHubTable(extraHubTables_[i],
mvSubGraphMap, // IN/OUT
querySubGraphMap, // IN/OUT
extraHubTableWasAdded) == FALSE)
return FALSE;
} // for
// Keep looping as long as there are extra-hub tables that are not connected,
// and as long as we keep adding them.
if (!extraHubTableWasAdded && extraHubTables_.entries() > 0)
{
logMVWasDisqualified1("Extra hub table %s is needed but cannot be matched.",
extraHubTables_[0]->data());
return FALSE;
}
// assertLogAndThrow(extraHubTableWasAdded, QRLogicException,
// "Extra-hub table is not connected to the hub.");
} while (extraHubTables_.entries() > 0);
// Update the MV new subGraphMap
mvSubGraphMap_ = mvSubGraphMap;
// We have added at least one extra-hub table -
// now we need to reorg the JBBSubsets accordingly.
MVCandidatesForJBBPtr jbb = getJbbSubset()->getJbbCandidates();
MVCandidatesForJBBSubsetPtr newJbbSubset = NULL;
QRJoinSubGraphPtr querySubGraph = querySubGraphMap->getSubGraph();
if (jbb->contains(querySubGraph))
{
// The JBBSubset with the new extra-hub tables already exists.
newJbbSubset = jbb->getJbbSubsetFor(querySubGraph);
}
else
{
// Need to create a new JBBSubset.
newJbbSubset = new (heap_) MVCandidatesForJBBSubset(jbb, ADD_MEMCHECK_ARGS(heap_));
newJbbSubset->setSubGraphMap(querySubGraphMap);
// Add the new JbbSubset to the JBB.
jbb->insert(newJbbSubset);
}
// Move the candidate from the current JbbSubset to the new one.
getJbbSubset()->remove(this);
newJbbSubset->insert(this);
setJbbSubset(newJbbSubset);
return TRUE;
} // CheckExtraHubTables()
