/**
* Clean up after consuming indexed tuples.
*/
void ElasticIndexReadContext::deleteStreamedTuples()
{
// Delete the indexed tuples that were streamed.
// Undo token release will cause the index to delete the corresponding items
// via notifications.
m_iter->reset();
TableTuple tuple;
while (m_iter->next(tuple)) {
if (!tuple.isPendingDelete()) {
m_surgeon.deleteTuple(tuple);
}
}
}
/**
* Clean up after consuming indexed tuples.
*/
void ElasticIndexReadContext::deleteStreamedTuples()
{
// Delete the indexed tuples that were streamed.
// Undo token release will cause the index to delete the corresponding items
// via notifications.
DRTupleStreamDisableGuard guard(ExecutorContext::getExecutorContext()->drStream(),
ExecutorContext::getExecutorContext()->drReplicatedStream());
m_iter->reset();
TableTuple tuple;
while (m_iter->next(tuple)) {
if (!tuple.isPendingDelete()) {
m_surgeon.deleteTuple(tuple);
}
}
}
/**
* Clean up after consuming indexed tuples.
*/
void ElasticIndexReadContext::deleteStreamedTuples()
{
// Delete the indexed tuples that were streamed.
// Undo token release will cause the index to delete the corresponding items
// via notifications.
ExecutorContext::getExecutorContext()->drStream()->m_enabled = false;
//Not unused, but GCC doesn't think a destructor counts as use
class DisableDRGuard {
public:
~DisableDRGuard() {
ExecutorContext::getExecutorContext()->drStream()->m_enabled = true;
}
} __attribute__((unused)) guard;
m_iter->reset();
TableTuple tuple;
while (m_iter->next(tuple)) {
if (!tuple.isPendingDelete()) {
m_surgeon.deleteTuple(tuple);
}
}
}
bool IndexScanExecutor::p_execute(const NValueArray ¶ms)
{
assert(m_node);
assert(m_node == dynamic_cast<IndexScanPlanNode*>(m_abstractNode));
// update local target table with its most recent reference
Table* targetTable = m_node->getTargetTable();
TableIndex *tableIndex = targetTable->index(m_node->getTargetIndexName());
IndexCursor indexCursor(tableIndex->getTupleSchema());
TableTuple searchKey(tableIndex->getKeySchema());
searchKey.moveNoHeader(m_searchKeyBackingStore);
assert(m_lookupType != INDEX_LOOKUP_TYPE_EQ ||
searchKey.getSchema()->columnCount() == m_numOfSearchkeys);
int activeNumOfSearchKeys = m_numOfSearchkeys;
IndexLookupType localLookupType = m_lookupType;
SortDirectionType localSortDirection = m_sortDirection;
//
// INLINE LIMIT
//
LimitPlanNode* limit_node = dynamic_cast<LimitPlanNode*>(m_abstractNode->getInlinePlanNode(PLAN_NODE_TYPE_LIMIT));
TableTuple temp_tuple;
ProgressMonitorProxy pmp(m_engine, this);
if (m_aggExec != NULL) {
const TupleSchema * inputSchema = tableIndex->getTupleSchema();
if (m_projectionNode != NULL) {
inputSchema = m_projectionNode->getOutputTable()->schema();
}
temp_tuple = m_aggExec->p_execute_init(params, &pmp, inputSchema, m_outputTable);
} else {
temp_tuple = m_outputTable->tempTuple();
}
// Short-circuit an empty scan
if (m_node->isEmptyScan()) {
VOLT_DEBUG ("Empty Index Scan :\n %s", m_outputTable->debug().c_str());
if (m_aggExec != NULL) {
m_aggExec->p_execute_finish();
}
return true;
}
//
// SEARCH KEY
//
bool earlyReturnForSearchKeyOutOfRange = false;
searchKey.setAllNulls();
VOLT_TRACE("Initial (all null) search key: '%s'", searchKey.debugNoHeader().c_str());
for (int ctr = 0; ctr < activeNumOfSearchKeys; ctr++) {
NValue candidateValue = m_searchKeyArray[ctr]->eval(NULL, NULL);
if (candidateValue.isNull()) {
// when any part of the search key is NULL, the result is false when it compares to anything.
// do early return optimization, our index comparator may not handle null comparison correctly.
earlyReturnForSearchKeyOutOfRange = true;
break;
}
try {
searchKey.setNValue(ctr, candidateValue);
}
catch (const SQLException &e) {
// This next bit of logic handles underflow, overflow and search key length
// exceeding variable length column size (variable lenght mismatch) when
// setting up the search keys.
// e.g. TINYINT > 200 or INT <= 6000000000
// VarChar(3 bytes) < "abcd" or VarChar(3) > "abbd"
// re-throw if not an overflow, underflow or variable length mismatch
// currently, it's expected to always be an overflow or underflow
if ((e.getInternalFlags() & (SQLException::TYPE_OVERFLOW | SQLException::TYPE_UNDERFLOW | SQLException::TYPE_VAR_LENGTH_MISMATCH)) == 0) {
throw e;
}
// handle the case where this is a comparison, rather than equality match
// comparison is the only place where the executor might return matching tuples
// e.g. TINYINT < 1000 should return all values
if ((localLookupType != INDEX_LOOKUP_TYPE_EQ) &&
(ctr == (activeNumOfSearchKeys - 1))) {
if (e.getInternalFlags() & SQLException::TYPE_OVERFLOW) {
if ((localLookupType == INDEX_LOOKUP_TYPE_GT) ||
(localLookupType == INDEX_LOOKUP_TYPE_GTE)) {
// gt or gte when key overflows returns nothing except inline agg
earlyReturnForSearchKeyOutOfRange = true;
break;
}
else {
// for overflow on reverse scan, we need to
// do a forward scan to find the correct start
// point, which is exactly what LTE would do.
// so, set the lookupType to LTE and the missing
// searchkey will be handled by extra post filters
localLookupType = INDEX_LOOKUP_TYPE_LTE;
}
}
if (e.getInternalFlags() & SQLException::TYPE_UNDERFLOW) {
if ((localLookupType == INDEX_LOOKUP_TYPE_LT) ||
(localLookupType == INDEX_LOOKUP_TYPE_LTE)) {
// lt or lte when key underflows returns nothing except inline agg
earlyReturnForSearchKeyOutOfRange = true;
break;
}
else {
// don't allow GTE because it breaks null handling
localLookupType = INDEX_LOOKUP_TYPE_GT;
}
}
if (e.getInternalFlags() & SQLException::TYPE_VAR_LENGTH_MISMATCH) {
// shrink the search key and add the updated key to search key table tuple
searchKey.shrinkAndSetNValue(ctr, candidateValue);
// search will be performed on shrinked key, so update lookup operation
// to account for it
switch (localLookupType) {
case INDEX_LOOKUP_TYPE_LT:
case INDEX_LOOKUP_TYPE_LTE:
localLookupType = INDEX_LOOKUP_TYPE_LTE;
break;
case INDEX_LOOKUP_TYPE_GT:
case INDEX_LOOKUP_TYPE_GTE:
localLookupType = INDEX_LOOKUP_TYPE_GT;
break;
default:
assert(!"IndexScanExecutor::p_execute - can't index on not equals");
return false;
}
}
// if here, means all tuples with the previous searchkey
// columns need to be scanned. Note, if only one column,
// then all tuples will be scanned. Only exception to this
// case is setting of search key in search tuple was due
// to search key length exceeding the search column length
// of variable length type
if (!(e.getInternalFlags() & SQLException::TYPE_VAR_LENGTH_MISMATCH)) {
// for variable length mismatch error, the needed search key to perform the search
// has been generated and added to the search tuple. So no need to decrement
// activeNumOfSearchKeys
activeNumOfSearchKeys--;
}
if (localSortDirection == SORT_DIRECTION_TYPE_INVALID) {
localSortDirection = SORT_DIRECTION_TYPE_ASC;
}
}
// if a EQ comparison is out of range, then return no tuples
else {
earlyReturnForSearchKeyOutOfRange = true;
break;
}
break;
}
}
if (earlyReturnForSearchKeyOutOfRange) {
if (m_aggExec != NULL) {
m_aggExec->p_execute_finish();
}
return true;
}
assert((activeNumOfSearchKeys == 0) || (searchKey.getSchema()->columnCount() > 0));
VOLT_TRACE("Search key after substitutions: '%s', # of active search keys: %d", searchKey.debugNoHeader().c_str(), activeNumOfSearchKeys);
//
// END EXPRESSION
//
AbstractExpression* end_expression = m_node->getEndExpression();
if (end_expression != NULL) {
VOLT_DEBUG("End Expression:\n%s", end_expression->debug(true).c_str());
}
//
// POST EXPRESSION
//
AbstractExpression* post_expression = m_node->getPredicate();
if (post_expression != NULL) {
VOLT_DEBUG("Post Expression:\n%s", post_expression->debug(true).c_str());
}
// INITIAL EXPRESSION
AbstractExpression* initial_expression = m_node->getInitialExpression();
if (initial_expression != NULL) {
VOLT_DEBUG("Initial Expression:\n%s", initial_expression->debug(true).c_str());
}
//
// SKIP NULL EXPRESSION
//
AbstractExpression* skipNullExpr = m_node->getSkipNullPredicate();
// For reverse scan edge case NULL values and forward scan underflow case.
if (skipNullExpr != NULL) {
VOLT_DEBUG("COUNT NULL Expression:\n%s", skipNullExpr->debug(true).c_str());
}
//
// An index scan has three parts:
// (1) Lookup tuples using the search key
// (2) For each tuple that comes back, check whether the
// end_expression is false.
// If it is, then we stop scanning. Otherwise...
// (3) Check whether the tuple satisfies the post expression.
// If it does, then add it to the output table
//
// Use our search key to prime the index iterator
// Now loop through each tuple given to us by the iterator
//
TableTuple tuple;
if (activeNumOfSearchKeys > 0) {
VOLT_TRACE("INDEX_LOOKUP_TYPE(%d) m_numSearchkeys(%d) key:%s",
localLookupType, activeNumOfSearchKeys, searchKey.debugNoHeader().c_str());
if (localLookupType == INDEX_LOOKUP_TYPE_EQ) {
tableIndex->moveToKey(&searchKey, indexCursor);
}
else if (localLookupType == INDEX_LOOKUP_TYPE_GT) {
tableIndex->moveToGreaterThanKey(&searchKey, indexCursor);
}
else if (localLookupType == INDEX_LOOKUP_TYPE_GTE) {
tableIndex->moveToKeyOrGreater(&searchKey, indexCursor);
}
else if (localLookupType == INDEX_LOOKUP_TYPE_LT) {
tableIndex->moveToLessThanKey(&searchKey, indexCursor);
}
else if (localLookupType == INDEX_LOOKUP_TYPE_LTE) {
// find the entry whose key is greater than search key,
// do a forward scan using initialExpr to find the correct
// start point to do reverse scan
bool isEnd = tableIndex->moveToGreaterThanKey(&searchKey, indexCursor);
if (isEnd) {
tableIndex->moveToEnd(false, indexCursor);
}
else {
while (!(tuple = tableIndex->nextValue(indexCursor)).isNullTuple()) {
pmp.countdownProgress();
if (initial_expression != NULL && !initial_expression->eval(&tuple, NULL).isTrue()) {
// just passed the first failed entry, so move 2 backward
tableIndex->moveToBeforePriorEntry(indexCursor);
break;
}
}
if (tuple.isNullTuple()) {
tableIndex->moveToEnd(false, indexCursor);
}
}
}
else {
return false;
}
}
else {
bool toStartActually = (localSortDirection != SORT_DIRECTION_TYPE_DESC);
tableIndex->moveToEnd(toStartActually, indexCursor);
}
int tuple_ctr = 0;
int tuples_skipped = 0; // for offset
int limit = -1;
int offset = -1;
if (limit_node != NULL) {
limit_node->getLimitAndOffsetByReference(params, limit, offset);
}
//
// We have to different nextValue() methods for different lookup types
//
while ((limit == -1 || tuple_ctr < limit) &&
((localLookupType == INDEX_LOOKUP_TYPE_EQ &&
!(tuple = tableIndex->nextValueAtKey(indexCursor)).isNullTuple()) ||
((localLookupType != INDEX_LOOKUP_TYPE_EQ || activeNumOfSearchKeys == 0) &&
!(tuple = tableIndex->nextValue(indexCursor)).isNullTuple()))) {
if (tuple.isPendingDelete()) {
continue;
}
VOLT_TRACE("LOOPING in indexscan: tuple: '%s'\n", tuple.debug("tablename").c_str());
pmp.countdownProgress();
//
// First check to eliminate the null index rows for UNDERFLOW case only
//
if (skipNullExpr != NULL) {
if (skipNullExpr->eval(&tuple, NULL).isTrue()) {
VOLT_DEBUG("Index scan: find out null rows or columns.");
continue;
} else {
skipNullExpr = NULL;
}
}
//
// First check whether the end_expression is now false
//
if (end_expression != NULL && !end_expression->eval(&tuple, NULL).isTrue()) {
VOLT_TRACE("End Expression evaluated to false, stopping scan");
break;
}
//
// Then apply our post-predicate to do further filtering
//
if (post_expression == NULL || post_expression->eval(&tuple, NULL).isTrue()) {
//
// INLINE OFFSET
//
if (tuples_skipped < offset)
{
tuples_skipped++;
continue;
}
tuple_ctr++;
if (m_projector.numSteps() > 0) {
m_projector.exec(temp_tuple, tuple);
if (m_aggExec != NULL) {
if (m_aggExec->p_execute_tuple(temp_tuple)) {
break;
}
} else {
m_outputTable->insertTupleNonVirtual(temp_tuple);
}
}
else
{
if (m_aggExec != NULL) {
if (m_aggExec->p_execute_tuple(tuple)) {
break;
}
} else {
//
// Straight Insert
//
m_outputTable->insertTupleNonVirtual(tuple);
}
}
pmp.countdownProgress();
}
}
if (m_aggExec != NULL) {
m_aggExec->p_execute_finish();
}
VOLT_DEBUG ("Index Scanned :\n %s", m_outputTable->debug().c_str());
return true;
}
