Fennel: LhxHashTableReader Class Reference (original) (raw)
#include <[LhxHashTable.h](LhxHashTable%5F8h-source.html)>
| Public Member Functions | |
|---|---|
| void | init (LhxHashTable *hashTableInit, LhxHashInfo const &hashInfo, uint buildInputIndex) |
| Initialize the hash table reader. | |
| void | bindKey (PBuffer key) |
| Bind this reader to a certain key. | |
| void | bindUnMatched () |
| Bind this reader to unmatched keys. | |
| bool | getNext (TupleData &outputTuple) |
| Get the next outputTuple. | |
| LhxHashTable * | getHashTable () |
| Private Member Functions | |
| bool | advanceSlot () |
| Locate the next slot to produce tuples from. | |
| bool | advanceKey () |
| Locate the next key to produce tuples from. | |
| bool | advanceData () |
| Locate the next data to produce tuples from. | |
| void | produceTuple (TupleData &outputTuple) |
| Produce the curKey + curData into outputTuple. | |
| void | bind (PBuffer key) |
| Helper function for bindKey() and bindUnMatched(). | |
| Private Attributes | |
| LhxHashTable * | hashTable |
| Underlying hash table to read from. | |
| bool | isGroupBy |
| Marks if this hash table is built for aggregation. | |
| PBuffer * | curSlot |
| Current read location. | |
| PBuffer | curKey |
| PBuffer | curData |
| PBuffer | boundKey |
| If not NULL, only read tuple with matching keys. | |
| bool | returnUnMatched |
| If true, only return tuples with unmatched keys. | |
| bool | isPositioned |
| Whether reader is positioned. | |
| LhxHashKeyAccessor | hashKeyAccessor |
| Accessors for the content of this hash table. | |
| LhxHashDataAccessor | hashDataAccessor |
| TupleProjection | keyColsAndAggsProj |
| Fields in the outputTuple that will hold keyCols and Aggs, and data columns. | |
| TupleProjection | dataProj |
Detailed Description
Definition at line 908 of file LhxHashTable.h.
Member Function Documentation
| bool LhxHashTableReader::advanceSlot | ( | | ) | [private] | | ------------------------------------ | - | | - | ----------- |
Locate the next slot to produce tuples from.
Set up the curKey and curData pointers.
Returns:
false if there is no more slots with keys.
Definition at line 1019 of file LhxHashTable.cpp.
References boundKey, curData, curKey, curSlot, LhxHashKeyAccessor::getFirstData(), LhxHashTable::getFirstSlot(), LhxHashNodeAccessor::getNext(), LhxHashTable::getNextSlot(), hashDataAccessor, hashKeyAccessor, hashTable, isGroupBy, LhxHashKeyAccessor::isMatched(), isPositioned, returnUnMatched, LhxHashDataAccessor::setCurrent(), and LhxHashKeyAccessor::setCurrent().
Referenced by getNext().
| bool LhxHashTableReader::advanceKey | ( | | ) | [private] | | ----------------------------------- | - | | - | ----------- |
Locate the next key to produce tuples from.
Set up the curKey and curData pointers.
Returns:
false if there is no more keys in the same slot.
Definition at line 1083 of file LhxHashTable.cpp.
References curData, curKey, LhxHashKeyAccessor::getFirstData(), LhxHashNodeAccessor::getNext(), hashDataAccessor, hashKeyAccessor, isGroupBy, LhxHashKeyAccessor::isMatched(), returnUnMatched, LhxHashDataAccessor::setCurrent(), and LhxHashKeyAccessor::setCurrent().
Referenced by getNext().
| bool LhxHashTableReader::advanceData | ( | | ) | [private] | | ------------------------------------ | - | | - | ----------- |
| void LhxHashTableReader::produceTuple | ( | TupleData & | outputTuple | ) | [private] |
|---|
| void LhxHashTableReader::bind | ( | PBuffer | key | ) | [inline, private] |
|---|
Initialize the hash table reader.
Parameters:
| [in] | hashTableInit | the underlying hash table to read from |
|---|---|---|
| [in] | hashInfo | |
| [in] | buildInputIndex | which input is the build side. |
Definition at line 1132 of file LhxHashTable.cpp.
References LhxHashInfo::aggsProj, bindKey(), LhxHashInfo::dataProj, dataProj, hashDataAccessor, hashKeyAccessor, hashTable, LhxHashDataAccessor::init(), LhxHashKeyAccessor::init(), LhxHashInfo::inputDesc, isGroupBy, LhxHashTable::isHashGroupBy(), keyColsAndAggsProj, and LhxHashInfo::keyProj.
Referenced by LhxJoinExecStream::execute(), LhxAggExecStream::execute(), LhxPartitionWriter::open(), LhxJoinExecStream::open(), LhxAggExecStream::open(), LhxHashTableTest::testInsert(), and LhxHashTableTest::writeHashTable().
| void LhxHashTableReader::bindKey | ( | PBuffer | key | ) | [inline] |
|---|
| void LhxHashTableReader::bindUnMatched | ( | | ) | [inline] | | -------------------------------------- | - | | - | ---------- |
| bool LhxHashTableReader::getNext | ( | TupleData & | outputTuple | ) |
|---|
Get the next outputTuple.
Parameters:
Returns:
false if no more tuples to output.
Definition at line 1190 of file LhxHashTable.cpp.
References advanceData(), advanceKey(), advanceSlot(), boundKey, isPositioned, produceTuple(), and returnUnMatched.
Referenced by LhxPartitionWriter::aggAndMarshalTuple(), LhxPartitionWriter::close(), LhxJoinExecStream::execute(), LhxAggExecStream::execute(), LhxHashTableTest::testInsert(), and LhxHashTableTest::writeHashTable().
01191 {
01192 if () {
01193 assert (!(boundKey && returnUnMatched));
01194
01195
01196
01197
01198 if (()) {
01199
01200
01201
01202 return false;
01203 }
01204 produceTuple(outputTuple);
01205 isPositioned = true;
01206 return true;
01207 }
01208
01209 if (advanceData()) {
01210 produceTuple(outputTuple);
01211 return true;
01212 } else {
01213 if (boundKey) {
01214
01215
01216
01217 return false;
01218 } else {
01219
01220
01221
01222 if (advanceKey()) {
01223 produceTuple(outputTuple);
01224 return true;
01225 } else {
01226
01227
01228
01229
01230 if (advanceSlot()) {
01231 produceTuple(outputTuple);
01232 return true;
01233 } else {
01234 return false;
01235 }
01236 }
01237 }
01238 }
01239 }
| LhxHashTable * LhxHashTableReader::getHashTable | ( | | ) | [inline] | | -------------------------------------------------------------------------- | - | | - | ---------- |
Member Data Documentation
Marks if this hash table is built for aggregation.
Aggregating hash table only contains keys (group by keys plus aggregates) and does not contain data portion. The reader behavior will thus be different from reading a hash table built for joins.
Definition at line 922 of file LhxHashTable.h.
Referenced by advanceData(), advanceKey(), advanceSlot(), init(), and produceTuple().
Fields in the outputTuple that will hold keyCols and Aggs, and data columns.
output tuple should have the same shape as outputTupleDesc used in the init() method.
Definition at line 963 of file LhxHashTable.h.
Referenced by init(), and produceTuple().
The documentation for this class was generated from the following files:
- /home/pub/open/dev/fennel/hashexe/LhxHashTable.h
- /home/pub/open/dev/fennel/hashexe/LhxHashTable.cpp
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