mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-21 15:12:02 +00:00
Add new index data skipping minmax index format for proper Nullable support
Note, that it cannot be done w/o new extension, since index does not have any header. v2: use IDisk interface for existence check v3: remove extra file existence check v4: fix MATERIALIZE INDEX
This commit is contained in:
parent
560e71dcfa
commit
038241b6ed
@ -1663,7 +1663,12 @@ NameToNameVector MergeTreeDataMergerMutator::collectFilesForRenames(
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{
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if (command.type == MutationCommand::Type::DROP_INDEX)
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{
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if (source_part->checksums.has(INDEX_FILE_PREFIX + command.column_name + ".idx"))
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if (source_part->checksums.has(INDEX_FILE_PREFIX + command.column_name + ".idx2"))
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{
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rename_vector.emplace_back(INDEX_FILE_PREFIX + command.column_name + ".idx2", "");
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rename_vector.emplace_back(INDEX_FILE_PREFIX + command.column_name + mrk_extension, "");
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}
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else if (source_part->checksums.has(INDEX_FILE_PREFIX + command.column_name + ".idx"))
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{
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rename_vector.emplace_back(INDEX_FILE_PREFIX + command.column_name + ".idx", "");
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rename_vector.emplace_back(INDEX_FILE_PREFIX + command.column_name + mrk_extension, "");
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@ -1749,6 +1754,7 @@ NameSet MergeTreeDataMergerMutator::collectFilesToSkip(
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for (const auto & index : indices_to_recalc)
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{
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files_to_skip.insert(index->getFileName() + ".idx");
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files_to_skip.insert(index->getFileName() + ".idx2");
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files_to_skip.insert(index->getFileName() + mrk_extension);
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}
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for (const auto & projection : projections_to_recalc)
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@ -1893,8 +1899,11 @@ std::set<MergeTreeIndexPtr> MergeTreeDataMergerMutator::getIndicesToRecalculate(
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{
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const auto & index = indices[i];
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bool has_index =
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source_part->checksums.has(INDEX_FILE_PREFIX + index.name + ".idx") ||
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source_part->checksums.has(INDEX_FILE_PREFIX + index.name + ".idx2");
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// If we ask to materialize and it already exists
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if (!source_part->checksums.has(INDEX_FILE_PREFIX + index.name + ".idx") && materialized_indices.count(index.name))
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if (!has_index && materialized_indices.count(index.name))
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{
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if (indices_to_recalc.insert(index_factory.get(index)).second)
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{
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@ -9,11 +9,6 @@ namespace ErrorCodes
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extern const int LOGICAL_ERROR;
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}
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namespace
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{
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constexpr auto INDEX_FILE_EXTENSION = ".idx";
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}
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void MergeTreeDataPartWriterOnDisk::Stream::finalize()
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{
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compressed.next();
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@ -165,7 +160,7 @@ void MergeTreeDataPartWriterOnDisk::initSkipIndices()
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std::make_unique<MergeTreeDataPartWriterOnDisk::Stream>(
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stream_name,
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data_part->volume->getDisk(),
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part_path + stream_name, INDEX_FILE_EXTENSION,
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part_path + stream_name, index_helper->getSerializedFileExtension(),
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part_path + stream_name, marks_file_extension,
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default_codec, settings.max_compress_block_size));
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skip_indices_aggregators.push_back(index_helper->createIndexAggregator());
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@ -1457,9 +1457,10 @@ MarkRanges MergeTreeDataSelectExecutor::filterMarksUsingIndex(
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size_t & granules_dropped,
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Poco::Logger * log)
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{
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if (!part->volume->getDisk()->exists(part->getFullRelativePath() + index_helper->getFileName() + ".idx"))
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const std::string & path_prefix = part->getFullRelativePath() + index_helper->getFileName();
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if (!index_helper->getDeserializedFormat(part->volume->getDisk(), path_prefix))
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{
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LOG_DEBUG(log, "File for index {} does not exist. Skipping it.", backQuote(index_helper->index.name));
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LOG_DEBUG(log, "File for index {} does not exist ({}.*). Skipping it.", backQuote(index_helper->index.name), path_prefix);
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return ranges;
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}
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@ -101,14 +101,17 @@ MergeTreeIndexGranuleFullText::MergeTreeIndexGranuleFullText(
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void MergeTreeIndexGranuleFullText::serializeBinary(WriteBuffer & ostr) const
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{
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if (empty())
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throw Exception("Attempt to write empty fulltext index " + backQuote(index_name), ErrorCodes::LOGICAL_ERROR);
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Attempt to write empty fulltext index {}.", backQuote(index_name));
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for (const auto & bloom_filter : bloom_filters)
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ostr.write(reinterpret_cast<const char *>(bloom_filter.getFilter().data()), params.filter_size);
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}
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void MergeTreeIndexGranuleFullText::deserializeBinary(ReadBuffer & istr)
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void MergeTreeIndexGranuleFullText::deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version)
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{
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if (version != 1)
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Unknown index version {}.", version);
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for (auto & bloom_filter : bloom_filters)
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{
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istr.read(reinterpret_cast<char *>(
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@ -45,7 +45,7 @@ struct MergeTreeIndexGranuleFullText final : public IMergeTreeIndexGranule
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~MergeTreeIndexGranuleFullText() override = default;
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void serializeBinary(WriteBuffer & ostr) const override;
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void deserializeBinary(ReadBuffer & istr) override;
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void deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version) override;
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bool empty() const override { return !has_elems; }
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@ -84,10 +84,12 @@ bool MergeTreeIndexGranuleBloomFilter::empty() const
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return !total_rows;
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}
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void MergeTreeIndexGranuleBloomFilter::deserializeBinary(ReadBuffer & istr)
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void MergeTreeIndexGranuleBloomFilter::deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version)
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{
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if (!empty())
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throw Exception("Cannot read data to a non-empty bloom filter index.", ErrorCodes::LOGICAL_ERROR);
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Cannot read data to a non-empty bloom filter index.");
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if (version != 1)
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Unknown index version {}.", version);
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readVarUInt(total_rows, istr);
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for (auto & filter : bloom_filters)
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@ -102,7 +104,7 @@ void MergeTreeIndexGranuleBloomFilter::deserializeBinary(ReadBuffer & istr)
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void MergeTreeIndexGranuleBloomFilter::serializeBinary(WriteBuffer & ostr) const
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{
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if (empty())
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throw Exception("Attempt to write empty bloom filter index.", ErrorCodes::LOGICAL_ERROR);
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Attempt to write empty bloom filter index.");
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static size_t atom_size = 8;
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writeVarUInt(total_rows, ostr);
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@ -16,8 +16,7 @@ public:
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bool empty() const override;
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void serializeBinary(WriteBuffer & ostr) const override;
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void deserializeBinary(ReadBuffer & istr) override;
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void deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version) override;
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const std::vector<BloomFilterPtr> & getFilters() const { return bloom_filters; }
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@ -40,28 +40,12 @@ void MergeTreeIndexGranuleMinMax::serializeBinary(WriteBuffer & ostr) const
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const DataTypePtr & type = index_sample_block.getByPosition(i).type;
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auto serialization = type->getDefaultSerialization();
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if (!type->isNullable())
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{
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serialization->serializeBinary(hyperrectangle[i].left, ostr);
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serialization->serializeBinary(hyperrectangle[i].right, ostr);
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}
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else
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{
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/// NOTE: that this serialization differs from
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/// IMergeTreeDataPart::MinMaxIndex::store() due to preserve
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/// backward compatibility.
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bool is_null = hyperrectangle[i].left.isNull() || hyperrectangle[i].right.isNull(); // one is enough
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writeBinary(is_null, ostr);
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if (!is_null)
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{
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serialization->serializeBinary(hyperrectangle[i].left, ostr);
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serialization->serializeBinary(hyperrectangle[i].right, ostr);
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}
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}
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serialization->serializeBinary(hyperrectangle[i].left, ostr);
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serialization->serializeBinary(hyperrectangle[i].right, ostr);
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}
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}
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void MergeTreeIndexGranuleMinMax::deserializeBinary(ReadBuffer & istr)
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void MergeTreeIndexGranuleMinMax::deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version)
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{
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hyperrectangle.clear();
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Field min_val;
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@ -72,29 +56,53 @@ void MergeTreeIndexGranuleMinMax::deserializeBinary(ReadBuffer & istr)
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const DataTypePtr & type = index_sample_block.getByPosition(i).type;
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auto serialization = type->getDefaultSerialization();
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if (!type->isNullable())
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switch (version)
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{
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serialization->deserializeBinary(min_val, istr);
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serialization->deserializeBinary(max_val, istr);
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}
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else
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{
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/// NOTE: that this serialization differs from
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/// IMergeTreeDataPart::MinMaxIndex::load() due to preserve
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/// backward compatibility.
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bool is_null;
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readBinary(is_null, istr);
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if (!is_null)
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{
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case 1:
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if (!type->isNullable())
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{
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serialization->deserializeBinary(min_val, istr);
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serialization->deserializeBinary(max_val, istr);
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}
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else
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{
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/// NOTE: that this serialization differs from
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/// IMergeTreeDataPart::MinMaxIndex::load() to preserve
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/// backward compatibility.
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///
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/// But this is deprecated format, so this is OK.
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bool is_null;
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readBinary(is_null, istr);
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if (!is_null)
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{
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serialization->deserializeBinary(min_val, istr);
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serialization->deserializeBinary(max_val, istr);
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}
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else
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{
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min_val = Null();
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max_val = Null();
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}
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}
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break;
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/// New format with proper Nullable support for values that includes Null values
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case 2:
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serialization->deserializeBinary(min_val, istr);
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serialization->deserializeBinary(max_val, istr);
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}
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else
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{
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min_val = Null();
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max_val = Null();
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}
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// NULL_LAST
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if (min_val.isNull())
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min_val = PositiveInfinity();
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if (max_val.isNull())
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max_val = PositiveInfinity();
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break;
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default:
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Unknown index version {}.", version);
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}
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hyperrectangle.emplace_back(min_val, true, max_val, true);
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}
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}
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@ -203,6 +211,15 @@ bool MergeTreeIndexMinMax::mayBenefitFromIndexForIn(const ASTPtr & node) const
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return false;
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}
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MergeTreeIndexFormat MergeTreeIndexMinMax::getDeserializedFormat(const DiskPtr disk, const std::string & relative_path_prefix) const
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{
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if (disk->exists(relative_path_prefix + ".idx2"))
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return {2, ".idx2"};
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else if (disk->exists(relative_path_prefix + ".idx"))
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return {1, ".idx"};
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return {0 /* unknown */, ""};
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}
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MergeTreeIndexPtr minmaxIndexCreator(
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const IndexDescription & index)
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{
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@ -21,7 +21,7 @@ struct MergeTreeIndexGranuleMinMax final : public IMergeTreeIndexGranule
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~MergeTreeIndexGranuleMinMax() override = default;
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void serializeBinary(WriteBuffer & ostr) const override;
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void deserializeBinary(ReadBuffer & istr) override;
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void deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version) override;
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bool empty() const override { return hyperrectangle.empty(); }
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@ -81,6 +81,9 @@ public:
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const SelectQueryInfo & query, ContextPtr context) const override;
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bool mayBenefitFromIndexForIn(const ASTPtr & node) const override;
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const char* getSerializedFileExtension() const override { return ".idx2"; }
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MergeTreeIndexFormat getDeserializedFormat(const DiskPtr disk, const std::string & path_prefix) const override;
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};
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}
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@ -1,5 +1,29 @@
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#include <Storages/MergeTree/MergeTreeIndexReader.h>
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namespace
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{
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using namespace DB;
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std::unique_ptr<MergeTreeReaderStream> makeIndexReader(
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const std::string & extension,
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MergeTreeIndexPtr index,
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MergeTreeData::DataPartPtr part,
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size_t marks_count,
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const MarkRanges & all_mark_ranges,
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MergeTreeReaderSettings settings)
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{
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return std::make_unique<MergeTreeReaderStream>(
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part->volume->getDisk(),
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part->getFullRelativePath() + index->getFileName(), extension, marks_count,
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all_mark_ranges,
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std::move(settings), nullptr, nullptr,
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part->getFileSizeOrZero(index->getFileName() + extension),
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&part->index_granularity_info,
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ReadBufferFromFileBase::ProfileCallback{}, CLOCK_MONOTONIC_COARSE);
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}
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}
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namespace DB
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{
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@ -7,27 +31,28 @@ namespace DB
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MergeTreeIndexReader::MergeTreeIndexReader(
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MergeTreeIndexPtr index_, MergeTreeData::DataPartPtr part_, size_t marks_count_, const MarkRanges & all_mark_ranges_,
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MergeTreeReaderSettings settings)
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: index(index_), stream(
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part_->volume->getDisk(),
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part_->getFullRelativePath() + index->getFileName(), ".idx", marks_count_,
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all_mark_ranges_,
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std::move(settings), nullptr, nullptr,
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part_->getFileSizeOrZero(index->getFileName() + ".idx"),
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&part_->index_granularity_info,
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ReadBufferFromFileBase::ProfileCallback{}, CLOCK_MONOTONIC_COARSE)
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: index(index_)
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{
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stream.seekToStart();
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const std::string & path_prefix = part_->getFullRelativePath() + index->getFileName();
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auto index_format = index->getDeserializedFormat(part_->volume->getDisk(), path_prefix);
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stream = makeIndexReader(index_format.extension, index_, part_, marks_count_, all_mark_ranges_, std::move(settings));
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version = index_format.version;
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stream->seekToStart();
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}
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MergeTreeIndexReader::~MergeTreeIndexReader() = default;
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void MergeTreeIndexReader::seek(size_t mark)
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{
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stream.seekToMark(mark);
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stream->seekToMark(mark);
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}
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MergeTreeIndexGranulePtr MergeTreeIndexReader::read()
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{
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auto granule = index->createIndexGranule();
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granule->deserializeBinary(*stream.data_buffer);
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granule->deserializeBinary(*stream->data_buffer, version);
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return granule;
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}
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@ -1,5 +1,6 @@
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#pragma once
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#include <memory>
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#include <Storages/MergeTree/MergeTreeReaderStream.h>
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#include <Storages/MergeTree/MergeTreeIndices.h>
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#include <Storages/MergeTree/MergeTreeData.h>
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@ -16,6 +17,7 @@ public:
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size_t marks_count_,
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const MarkRanges & all_mark_ranges_,
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MergeTreeReaderSettings settings);
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~MergeTreeIndexReader();
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void seek(size_t mark);
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@ -23,7 +25,8 @@ public:
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private:
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MergeTreeIndexPtr index;
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MergeTreeReaderStream stream;
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std::unique_ptr<MergeTreeReaderStream> stream;
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uint8_t version = 0;
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};
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}
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@ -48,8 +48,7 @@ MergeTreeIndexGranuleSet::MergeTreeIndexGranuleSet(
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void MergeTreeIndexGranuleSet::serializeBinary(WriteBuffer & ostr) const
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{
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if (empty())
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throw Exception(
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"Attempt to write empty set index " + backQuote(index_name), ErrorCodes::LOGICAL_ERROR);
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Attempt to write empty set index {}.", backQuote(index_name));
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const auto & size_type = DataTypePtr(std::make_shared<DataTypeUInt64>());
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auto size_serialization = size_type->getDefaultSerialization();
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@ -80,8 +79,11 @@ void MergeTreeIndexGranuleSet::serializeBinary(WriteBuffer & ostr) const
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}
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}
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void MergeTreeIndexGranuleSet::deserializeBinary(ReadBuffer & istr)
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void MergeTreeIndexGranuleSet::deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version)
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{
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if (version != 1)
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throw Exception(ErrorCodes::LOGICAL_ERROR, "Unknown index version {}.", version);
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block.clear();
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Field field_rows;
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@ -28,7 +28,7 @@ struct MergeTreeIndexGranuleSet final : public IMergeTreeIndexGranule
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MutableColumns && columns_);
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void serializeBinary(WriteBuffer & ostr) const override;
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void deserializeBinary(ReadBuffer & istr) override;
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void deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version) override;
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size_t size() const { return block.rows(); }
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bool empty() const override { return !size(); }
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@ -4,6 +4,7 @@
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#include <unordered_map>
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#include <vector>
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#include <memory>
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#include <utility>
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#include <Core/Block.h>
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#include <Storages/StorageInMemoryMetadata.h>
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#include <Storages/MergeTree/MergeTreeDataPartChecksum.h>
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@ -17,13 +18,37 @@ constexpr auto INDEX_FILE_PREFIX = "skp_idx_";
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namespace DB
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{
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using MergeTreeIndexVersion = uint8_t;
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struct MergeTreeIndexFormat
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{
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MergeTreeIndexVersion version;
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const char* extension;
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operator bool() const { return version != 0; }
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};
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/// Stores some info about a single block of data.
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struct IMergeTreeIndexGranule
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{
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virtual ~IMergeTreeIndexGranule() = default;
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/// Serialize always last version.
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virtual void serializeBinary(WriteBuffer & ostr) const = 0;
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virtual void deserializeBinary(ReadBuffer & istr) = 0;
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/// Version of the index to deserialize:
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///
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/// - 2 -- minmax index for proper Nullable support,
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/// - 1 -- everything else.
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///
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/// Implementation is responsible for version check,
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/// and throw LOGICAL_ERROR in case of unsupported version.
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///
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||||
/// See also:
|
||||
/// - IMergeTreeIndex::getSerializedFileExtension()
|
||||
/// - IMergeTreeIndex::getDeserializedFormat()
|
||||
/// - MergeTreeDataMergerMutator::collectFilesToSkip()
|
||||
/// - MergeTreeDataMergerMutator::collectFilesForRenames()
|
||||
virtual void deserializeBinary(ReadBuffer & istr, MergeTreeIndexVersion version) = 0;
|
||||
|
||||
virtual bool empty() const = 0;
|
||||
};
|
||||
@ -73,9 +98,26 @@ struct IMergeTreeIndex
|
||||
|
||||
virtual ~IMergeTreeIndex() = default;
|
||||
|
||||
/// gets filename without extension
|
||||
/// Returns filename without extension.
|
||||
String getFileName() const { return INDEX_FILE_PREFIX + index.name; }
|
||||
|
||||
/// Returns extension for serialization.
|
||||
/// Reimplement if you want new index format.
|
||||
///
|
||||
/// NOTE: In case getSerializedFileExtension() is reimplemented,
|
||||
/// getDeserializedFormat() should be reimplemented too,
|
||||
/// and check all previous extensions too
|
||||
/// (to avoid breaking backward compatibility).
|
||||
virtual const char* getSerializedFileExtension() const { return ".idx"; }
|
||||
|
||||
/// Returns extension for deserialization.
|
||||
///
|
||||
/// Return pair<extension, version>.
|
||||
virtual MergeTreeIndexFormat getDeserializedFormat(const DiskPtr, const std::string & /* relative_path_prefix */) const
|
||||
{
|
||||
return {1, ".idx"};
|
||||
}
|
||||
|
||||
/// Checks whether the column is in data skipping index.
|
||||
virtual bool mayBenefitFromIndexForIn(const ASTPtr & node) const = 0;
|
||||
|
||||
|
@ -49,15 +49,11 @@ SET force_primary_key = 0;
|
||||
SELECT * FROM nullable_minmax_index ORDER BY k;
|
||||
SET max_rows_to_read = 6;
|
||||
SELECT * FROM nullable_minmax_index WHERE v IS NULL;
|
||||
-- NOTE: granuals with Null values cannot be filtred in data skipping indexes,
|
||||
-- due to backward compatibility
|
||||
SET max_rows_to_read = 0;
|
||||
SET max_rows_to_read = 8;
|
||||
SELECT * FROM nullable_minmax_index WHERE v IS NOT NULL;
|
||||
SET max_rows_to_read = 6;
|
||||
SELECT * FROM nullable_minmax_index WHERE v > 2;
|
||||
-- NOTE: granuals with Null values cannot be filtred in data skipping indexes,
|
||||
-- due to backward compatibility
|
||||
SET max_rows_to_read = 0;
|
||||
SET max_rows_to_read = 4;
|
||||
SELECT * FROM nullable_minmax_index WHERE v <= 2;
|
||||
|
||||
DROP TABLE nullable_key;
|
||||
|
Loading…
Reference in New Issue
Block a user