@Override
public Row next() {
if (TAP_NEXT_ENABLED) {
TAP_NEXT.in();
}
try {
if (CURSOR_LIFECYCLE_ENABLED) {
CursorLifecycle.checkIdleOrActive(this);
}
checkQueryCancelation();
Row row;
while (skipLeft > 0) {
if ((row = input.next()) == null) {
skipLeft = 0;
limitLeft = -1;
setIdle();
if (LOG_EXECUTION) {
LOG.debug("Limit_Default: skipLeft until complete yield null");
}
return null;
}
skipLeft--;
}
if (limitLeft < 0) {
setIdle();
if (LOG_EXECUTION) {
LOG.debug("Limit_Default: limitLeft < 0, yield null");
}
return null;
}
if (limitLeft == 0) {
setIdle();
if (LOG_EXECUTION) {
LOG.debug("Limit_Default: limitLeft == 0, yield null");
}
return null;
}
if ((row = input.next()) == null) {
limitLeft = -1;
setIdle();
if (LOG_EXECUTION) {
LOG.debug("Limit_Default: yield null");
}
return null;
}
--limitLeft;
if (LOG_EXECUTION) {
LOG.debug("Limit_Default: yield {}", row);
}
return row;
} finally {
if (TAP_NEXT_ENABLED) {
TAP_NEXT.out();
}
}
}
private boolean rowReallyHasMatch(Row row) {
// bindingPosition is used to hold onto a row for use during the evaluation of expressions
// during onPositiveCursor.open(). This is somewhat sleazy, but the alternative is to
// complicate the Select_BloomFilter API, requiring the caller to specify another binding
// position.
// It is safe to reuse the binding position in this way because the filter is extracted and
// stored
// in a field during open(), while the use of the binding position for use in the onPositive
// lookup
// occurs during next().
if (LOG_EXECUTION) {
LOG.debug("Select_BloomFilter: candidate {}", row);
}
TAP_CHECK.in();
try {
bindings.setRow(bindingPosition, row);
onPositiveBindingsCursor.reset(bindings);
onPositiveCursor.openTopLevel();
try {
return onPositiveCursor.next() != null;
} finally {
onPositiveCursor.closeTopLevel();
bindings.setRow(bindingPosition, null);
}
} finally {
TAP_CHECK.out();
}
}
@Override
public Row next() {
if (TAP_NEXT_ENABLED) {
TAP_NEXT.in();
}
try {
if (CURSOR_LIFECYCLE_ENABLED) {
CursorLifecycle.checkIdleOrActive(this);
}
Row row;
do {
row = inputCursor.next();
if (row == null) {
close();
} else if (!filter.maybePresent(hashProjectedRow(row)) || !rowReallyHasMatch(row)) {
row = null;
}
} while (!idle && row == null);
if (LOG_EXECUTION) {
LOG.debug("Select_BloomFilter: yield {}", row);
}
return row;
} finally {
if (TAP_NEXT_ENABLED) {
TAP_NEXT.out();
}
}
}
@Override
protected Row nextInputRow() {
BloomFilter filter = baseBindings.getBloomFilter(bindingPosition);
while (true) {
Row row = input.next();
if (row == null) {
return row;
}
if (filter.maybePresent(hashProjectedRow(row))) {
if (ExecutionBase.LOG_EXECUTION) {
LOG.debug("Select_BloomFilter: candidate {}", row);
}
return row;
}
}
}
