mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-28 02:21:59 +00:00
Add new dictionary layout (sparse_hashed) that is more memory efficient
With this new layout, sparsehash will be used over default HashMap, sparsehash is more memory efficient but it is also slower. So in a nutshell: - HashMap uses ~2x more memory then sparse_hash_map - HashMap ~2-2.5x faster then sparse_hash_map (tested on lots of input, and the most close to production was dictionary with 600KK hashes and UInt16 as value) TODO: - fix allocated memory calculation - getBufferSizeInBytes/getBufferSizeInCells interface - benchmarks v0: replace HashMap with google::sparse_hash_map v2: use google::sparse_hash_map only when <sparse> isset to true v3: replace attributes with different layout v4: use ch hash over std::hash
This commit is contained in:
parent
1fe79ad43c
commit
420089c301
@ -40,3 +40,5 @@ if(USE_POCO_MONGODB)
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endif()
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add_subdirectory(Embedded)
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target_include_directories(clickhouse_dictionaries SYSTEM PRIVATE ${SPARSEHASH_INCLUDE_DIR})
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@ -3,6 +3,23 @@
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#include "DictionaryBlockInputStream.h"
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#include "DictionaryFactory.h"
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namespace
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{
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/// google::sparse_hash_map
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template <class T> auto first(const T &lhs) -> decltype(lhs.first)
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{ return lhs.first; }
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template <class T> auto second(const T &lhs) -> decltype(lhs.second)
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{ return lhs.second; }
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/// HashMap
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template <class T> auto first(const T &lhs) -> decltype(lhs.getFirst())
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{ return lhs.getFirst(); }
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template <class T> auto second(const T &lhs) -> decltype(lhs.getSecond())
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{ return lhs.getSecond(); }
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}
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namespace DB
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{
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namespace ErrorCodes
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@ -21,12 +38,14 @@ HashedDictionary::HashedDictionary(
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DictionarySourcePtr source_ptr_,
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const DictionaryLifetime dict_lifetime_,
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bool require_nonempty_,
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bool sparse_,
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BlockPtr saved_block_)
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: name{name_}
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, dict_struct(dict_struct_)
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, source_ptr{std::move(source_ptr_)}
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, dict_lifetime(dict_lifetime_)
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, require_nonempty(require_nonempty_)
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, sparse(sparse_)
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, saved_block{std::move(saved_block_)}
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{
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createAttributes();
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@ -57,11 +76,10 @@ static inline HashedDictionary::Key getAt(const HashedDictionary::Key & value, c
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return value;
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}
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template <typename ChildType, typename AncestorType>
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void HashedDictionary::isInImpl(const ChildType & child_ids, const AncestorType & ancestor_ids, PaddedPODArray<UInt8> & out) const
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template <typename AttrType, typename ChildType, typename AncestorType>
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void HashedDictionary::isInAttrImpl(const AttrType & attr, const ChildType & child_ids, const AncestorType & ancestor_ids, PaddedPODArray<UInt8> & out) const
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{
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const auto null_value = std::get<UInt64>(hierarchical_attribute->null_values);
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const auto & attr = *std::get<CollectionPtrType<Key>>(hierarchical_attribute->maps);
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const auto rows = out.size();
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for (const auto row : ext::range(0, rows))
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@ -73,7 +91,7 @@ void HashedDictionary::isInImpl(const ChildType & child_ids, const AncestorType
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{
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auto it = attr.find(id);
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if (it != std::end(attr))
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id = it->getSecond();
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id = second(*it);
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else
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break;
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}
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@ -83,6 +101,13 @@ void HashedDictionary::isInImpl(const ChildType & child_ids, const AncestorType
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query_count.fetch_add(rows, std::memory_order_relaxed);
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}
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template <typename ChildType, typename AncestorType>
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void HashedDictionary::isInImpl(const ChildType & child_ids, const AncestorType & ancestor_ids, PaddedPODArray<UInt8> & out) const
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{
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if (!sparse)
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return isInAttrImpl(*std::get<CollectionPtrType<Key>>(hierarchical_attribute->maps), child_ids, ancestor_ids, out);
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return isInAttrImpl(*std::get<SparseCollectionPtrType<Key>>(hierarchical_attribute->sparse_maps), child_ids, ancestor_ids, out);
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}
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void HashedDictionary::isInVectorVector(
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const PaddedPODArray<Key> & child_ids, const PaddedPODArray<Key> & ancestor_ids, PaddedPODArray<UInt8> & out) const
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@ -407,9 +432,22 @@ void HashedDictionary::loadData()
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template <typename T>
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void HashedDictionary::addAttributeSize(const Attribute & attribute)
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{
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const auto & map_ref = std::get<CollectionPtrType<T>>(attribute.maps);
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bytes_allocated += sizeof(CollectionType<T>) + map_ref->getBufferSizeInBytes();
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bucket_count = map_ref->getBufferSizeInCells();
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if (!sparse)
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{
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const auto & map_ref = std::get<CollectionPtrType<T>>(attribute.maps);
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bytes_allocated += sizeof(CollectionType<T>) + map_ref->getBufferSizeInBytes();
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bucket_count = map_ref->getBufferSizeInCells();
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}
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else
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{
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const auto & map_ref = std::get<SparseCollectionPtrType<T>>(attribute.sparse_maps);
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bucket_count = map_ref->bucket_count();
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/** TODO: more accurate calculation */
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bytes_allocated += sizeof(CollectionType<T>);
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bytes_allocated += bucket_count;
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bytes_allocated += map_ref->size() * sizeof(Key) * sizeof(T);
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}
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}
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void HashedDictionary::calculateBytesAllocated()
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@ -479,12 +517,15 @@ template <typename T>
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void HashedDictionary::createAttributeImpl(Attribute & attribute, const Field & null_value)
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{
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attribute.null_values = T(null_value.get<NearestFieldType<T>>());
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attribute.maps = std::make_unique<CollectionType<T>>();
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if (!sparse)
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attribute.maps = std::make_unique<CollectionType<T>>();
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else
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attribute.sparse_maps = std::make_unique<SparseCollectionType<T>>();
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}
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HashedDictionary::Attribute HashedDictionary::createAttributeWithType(const AttributeUnderlyingType type, const Field & null_value)
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{
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Attribute attr{type, {}, {}, {}};
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Attribute attr{type, {}, {}, {}, {}};
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switch (type)
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{
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@ -535,7 +576,10 @@ HashedDictionary::Attribute HashedDictionary::createAttributeWithType(const Attr
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case AttributeUnderlyingType::utString:
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{
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attr.null_values = null_value.get<String>();
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attr.maps = std::make_unique<CollectionType<StringRef>>();
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if (!sparse)
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attr.maps = std::make_unique<CollectionType<StringRef>>();
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else
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attr.sparse_maps = std::make_unique<SparseCollectionType<StringRef>>();
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attr.string_arena = std::make_unique<Arena>();
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break;
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}
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@ -545,28 +589,43 @@ HashedDictionary::Attribute HashedDictionary::createAttributeWithType(const Attr
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}
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template <typename AttributeType, typename OutputType, typename ValueSetter, typename DefaultGetter>
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void HashedDictionary::getItemsImpl(
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const Attribute & attribute, const PaddedPODArray<Key> & ids, ValueSetter && set_value, DefaultGetter && get_default) const
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template <typename OutputType, typename AttrType, typename ValueSetter, typename DefaultGetter>
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void HashedDictionary::getItemsAttrImpl(
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const AttrType & attr, const PaddedPODArray<Key> & ids, ValueSetter && set_value, DefaultGetter && get_default) const
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{
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const auto & attr = *std::get<CollectionPtrType<AttributeType>>(attribute.maps);
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const auto rows = ext::size(ids);
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for (const auto i : ext::range(0, rows))
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{
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const auto it = attr.find(ids[i]);
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set_value(i, it != attr.end() ? static_cast<OutputType>(it->getSecond()) : get_default(i));
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set_value(i, it != attr.end() ? static_cast<OutputType>(second(*it)) : get_default(i));
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}
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query_count.fetch_add(rows, std::memory_order_relaxed);
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}
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template <typename AttributeType, typename OutputType, typename ValueSetter, typename DefaultGetter>
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void HashedDictionary::getItemsImpl(
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const Attribute & attribute, const PaddedPODArray<Key> & ids, ValueSetter && set_value, DefaultGetter && get_default) const
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{
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if (!sparse)
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return getItemsAttrImpl<OutputType>(*std::get<CollectionPtrType<AttributeType>>(attribute.maps), ids, set_value, get_default);
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return getItemsAttrImpl<OutputType>(*std::get<SparseCollectionPtrType<AttributeType>>(attribute.sparse_maps), ids, set_value, get_default);
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}
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template <typename T>
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bool HashedDictionary::setAttributeValueImpl(Attribute & attribute, const Key id, const T value)
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{
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auto & map = *std::get<CollectionPtrType<T>>(attribute.maps);
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return map.insert({id, value}).second;
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if (!sparse)
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{
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auto & map = *std::get<CollectionPtrType<T>>(attribute.maps);
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return map.insert({id, value}).second;
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}
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else
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{
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auto & map = *std::get<SparseCollectionPtrType<T>>(attribute.sparse_maps);
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return map.insert({id, value}).second;
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}
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}
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bool HashedDictionary::setAttributeValue(Attribute & attribute, const Key id, const Field & value)
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@ -605,10 +664,18 @@ bool HashedDictionary::setAttributeValue(Attribute & attribute, const Key id, co
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case AttributeUnderlyingType::utString:
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{
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auto & map = *std::get<CollectionPtrType<StringRef>>(attribute.maps);
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const auto & string = value.get<String>();
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const auto string_in_arena = attribute.string_arena->insert(string.data(), string.size());
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return map.insert({id, StringRef{string_in_arena, string.size()}}).second;
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if (!sparse)
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{
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auto & map = *std::get<CollectionPtrType<StringRef>>(attribute.maps);
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return map.insert({id, StringRef{string_in_arena, string.size()}}).second;
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}
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else
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{
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auto & map = *std::get<SparseCollectionPtrType<StringRef>>(attribute.sparse_maps);
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return map.insert({id, StringRef{string_in_arena, string.size()}}).second;
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}
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}
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}
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@ -636,18 +703,23 @@ void HashedDictionary::has(const Attribute & attribute, const PaddedPODArray<Key
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query_count.fetch_add(rows, std::memory_order_relaxed);
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}
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template <typename T>
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PaddedPODArray<HashedDictionary::Key> HashedDictionary::getIds(const Attribute & attribute) const
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template <typename T, typename AttrType>
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PaddedPODArray<HashedDictionary::Key> HashedDictionary::getIdsAttrImpl(const AttrType & attr) const
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{
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const HashMap<UInt64, T> & attr = *std::get<CollectionPtrType<T>>(attribute.maps);
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PaddedPODArray<Key> ids;
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ids.reserve(attr.size());
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for (const auto & value : attr)
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ids.push_back(value.getFirst());
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ids.push_back(first(value));
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return ids;
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}
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template <typename T>
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PaddedPODArray<HashedDictionary::Key> HashedDictionary::getIds(const Attribute & attribute) const
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{
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if (!sparse)
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return getIdsAttrImpl<T>(*std::get<CollectionPtrType<Key>>(attribute.maps));
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return getIdsAttrImpl<T>(*std::get<SparseCollectionPtrType<Key>>(attribute.sparse_maps));
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}
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PaddedPODArray<HashedDictionary::Key> HashedDictionary::getIds() const
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{
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@ -714,9 +786,11 @@ void registerDictionaryHashed(DictionaryFactory & factory)
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ErrorCodes::BAD_ARGUMENTS};
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const DictionaryLifetime dict_lifetime{config, config_prefix + ".lifetime"};
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const bool require_nonempty = config.getBool(config_prefix + ".require_nonempty", false);
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return std::make_unique<HashedDictionary>(name, dict_struct, std::move(source_ptr), dict_lifetime, require_nonempty);
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const bool sparse = name == "sparse_hashed";
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return std::make_unique<HashedDictionary>(name, dict_struct, std::move(source_ptr), dict_lifetime, require_nonempty, sparse);
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};
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factory.registerLayout("hashed", create_layout);
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factory.registerLayout("sparse_hashed", create_layout);
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}
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}
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@ -7,6 +7,7 @@
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#include <Columns/ColumnString.h>
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#include <Core/Block.h>
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#include <Common/HashTable/HashMap.h>
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#include <sparsehash/sparse_hash_map>
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#include <ext/range.h>
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#include "DictionaryStructure.h"
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#include "IDictionary.h"
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@ -26,6 +27,7 @@ public:
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DictionarySourcePtr source_ptr_,
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const DictionaryLifetime dict_lifetime_,
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bool require_nonempty_,
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bool sparse_,
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BlockPtr saved_block_ = nullptr);
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std::string getName() const override { return name; }
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@ -46,7 +48,7 @@ public:
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std::shared_ptr<const IExternalLoadable> clone() const override
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{
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return std::make_shared<HashedDictionary>(name, dict_struct, source_ptr->clone(), dict_lifetime, require_nonempty, saved_block);
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return std::make_shared<HashedDictionary>(name, dict_struct, source_ptr->clone(), dict_lifetime, require_nonempty, sparse, saved_block);
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}
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const IDictionarySource * getSource() const override { return source_ptr.get(); }
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@ -149,6 +151,11 @@ private:
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template <typename Value>
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using CollectionPtrType = std::unique_ptr<CollectionType<Value>>;
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template <typename Value>
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using SparseCollectionType = google::sparse_hash_map<UInt64, Value, DefaultHash<UInt64>>;
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template <typename Value>
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using SparseCollectionPtrType = std::unique_ptr<SparseCollectionType<Value>>;
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struct Attribute final
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{
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AttributeUnderlyingType type;
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@ -186,6 +193,23 @@ private:
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CollectionPtrType<Float64>,
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CollectionPtrType<StringRef>>
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maps;
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std::variant<
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SparseCollectionPtrType<UInt8>,
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SparseCollectionPtrType<UInt16>,
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SparseCollectionPtrType<UInt32>,
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SparseCollectionPtrType<UInt64>,
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SparseCollectionPtrType<UInt128>,
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SparseCollectionPtrType<Int8>,
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SparseCollectionPtrType<Int16>,
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SparseCollectionPtrType<Int32>,
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SparseCollectionPtrType<Int64>,
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SparseCollectionPtrType<Decimal32>,
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SparseCollectionPtrType<Decimal64>,
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SparseCollectionPtrType<Decimal128>,
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SparseCollectionPtrType<Float32>,
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SparseCollectionPtrType<Float64>,
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SparseCollectionPtrType<StringRef>>
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sparse_maps;
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std::unique_ptr<Arena> string_arena;
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};
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@ -207,6 +231,9 @@ private:
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Attribute createAttributeWithType(const AttributeUnderlyingType type, const Field & null_value);
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template <typename OutputType, typename AttrType, typename ValueSetter, typename DefaultGetter>
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void getItemsAttrImpl(
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const AttrType & attr, const PaddedPODArray<Key> & ids, ValueSetter && set_value, DefaultGetter && get_default) const;
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template <typename AttributeType, typename OutputType, typename ValueSetter, typename DefaultGetter>
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void getItemsImpl(
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const Attribute & attribute, const PaddedPODArray<Key> & ids, ValueSetter && set_value, DefaultGetter && get_default) const;
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@ -221,11 +248,15 @@ private:
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template <typename T>
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void has(const Attribute & attribute, const PaddedPODArray<Key> & ids, PaddedPODArray<UInt8> & out) const;
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template <typename T, typename AttrType>
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PaddedPODArray<Key> getIdsAttrImpl(const AttrType & attr) const;
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template <typename T>
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PaddedPODArray<Key> getIds(const Attribute & attribute) const;
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PaddedPODArray<Key> getIds() const;
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template <typename AttrType, typename ChildType, typename AncestorType>
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void isInAttrImpl(const AttrType & attr, const ChildType & child_ids, const AncestorType & ancestor_ids, PaddedPODArray<UInt8> & out) const;
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template <typename ChildType, typename AncestorType>
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void isInImpl(const ChildType & child_ids, const AncestorType & ancestor_ids, PaddedPODArray<UInt8> & out) const;
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@ -234,6 +265,7 @@ private:
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const DictionarySourcePtr source_ptr;
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const DictionaryLifetime dict_lifetime;
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const bool require_nonempty;
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const bool sparse;
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std::map<std::string, size_t> attribute_index_by_name;
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std::vector<Attribute> attributes;
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@ -33,7 +33,7 @@ if (OPENSSL_CRYPTO_LIBRARY)
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endif()
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target_include_directories(clickhouse_functions PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/include)
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target_include_directories(clickhouse_functions SYSTEM PRIVATE ${DIVIDE_INCLUDE_DIR} ${METROHASH_INCLUDE_DIR})
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target_include_directories(clickhouse_functions SYSTEM PRIVATE ${DIVIDE_INCLUDE_DIR} ${METROHASH_INCLUDE_DIR} ${SPARSEHASH_INCLUDE_DIR})
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if (CONSISTENT_HASHING_INCLUDE_DIR)
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target_include_directories (clickhouse_functions PRIVATE ${CONSISTENT_HASHING_INCLUDE_DIR})
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@ -125,6 +125,69 @@
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</structure>
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</dictionary>
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<dictionary>
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<name>hashed_sparse_ints</name>
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<source>
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<clickhouse>
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<host>localhost</host>
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<port>9000</port>
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<user>default</user>
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<password></password>
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<db>test_00950</db>
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<table>ints</table>
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</clickhouse>
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</source>
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<lifetime>0</lifetime>
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<layout>
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<sparse_hashed/>
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</layout>
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<structure>
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<id>
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<name>key</name>
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</id>
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<attribute>
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<name>i8</name>
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<type>Int8</type>
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<null_value>0</null_value>
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</attribute>
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<attribute>
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<name>i16</name>
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<type>Int16</type>
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<null_value>0</null_value>
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</attribute>
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<attribute>
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<name>i32</name>
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<type>Int32</type>
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<null_value>0</null_value>
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</attribute>
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<attribute>
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<name>i64</name>
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<type>Int64</type>
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<null_value>0</null_value>
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</attribute>
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<attribute>
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<name>u8</name>
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<type>UInt8</type>
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<null_value>0</null_value>
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</attribute>
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<attribute>
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<name>u16</name>
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<type>UInt16</type>
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<null_value>0</null_value>
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</attribute>
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<attribute>
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<name>u32</name>
|
||||
<type>UInt32</type>
|
||||
<null_value>0</null_value>
|
||||
</attribute>
|
||||
<attribute>
|
||||
<name>u64</name>
|
||||
<type>UInt64</type>
|
||||
<null_value>0</null_value>
|
||||
</attribute>
|
||||
</structure>
|
||||
</dictionary>
|
||||
|
||||
<dictionary>
|
||||
<name>cache_ints</name>
|
||||
<source>
|
||||
|
@ -4,6 +4,9 @@ dictGetOrDefault flat_ints 0 42 42 42 42 42 42 42 42
|
||||
dictGet hashed_ints 1 1 1 1 1 1 1 1 1
|
||||
dictGetOrDefault hashed_ints 1 1 1 1 1 1 1 1 1
|
||||
dictGetOrDefault hashed_ints 0 42 42 42 42 42 42 42 42
|
||||
dictGet hashed_sparse_ints 1 1 1 1 1 1 1 1 1
|
||||
dictGetOrDefault hashed_sparse_ints 1 1 1 1 1 1 1 1 1
|
||||
dictGetOrDefault hashed_sparse_ints 0 42 42 42 42 42 42 42 42
|
||||
dictGet cache_ints 1 1 1 1 1 1 1 1 1
|
||||
dictGetOrDefault cache_ints 1 1 1 1 1 1 1 1 1
|
||||
dictGetOrDefault cache_ints 0 42 42 42 42 42 42 42 42
|
||||
|
@ -69,6 +69,34 @@ select 'dictGetOrDefault', 'hashed_ints' as dict_name, toUInt64(0) as k,
|
||||
dictGetOrDefault(dict_name, 'u32', k, toUInt32(42)),
|
||||
dictGetOrDefault(dict_name, 'u64', k, toUInt64(42));
|
||||
|
||||
select 'dictGet', 'hashed_sparse_ints' as dict_name, toUInt64(1) as k,
|
||||
dictGet(dict_name, 'i8', k),
|
||||
dictGet(dict_name, 'i16', k),
|
||||
dictGet(dict_name, 'i32', k),
|
||||
dictGet(dict_name, 'i64', k),
|
||||
dictGet(dict_name, 'u8', k),
|
||||
dictGet(dict_name, 'u16', k),
|
||||
dictGet(dict_name, 'u32', k),
|
||||
dictGet(dict_name, 'u64', k);
|
||||
select 'dictGetOrDefault', 'hashed_sparse_ints' as dict_name, toUInt64(1) as k,
|
||||
dictGetOrDefault(dict_name, 'i8', k, toInt8(42)),
|
||||
dictGetOrDefault(dict_name, 'i16', k, toInt16(42)),
|
||||
dictGetOrDefault(dict_name, 'i32', k, toInt32(42)),
|
||||
dictGetOrDefault(dict_name, 'i64', k, toInt64(42)),
|
||||
dictGetOrDefault(dict_name, 'u8', k, toUInt8(42)),
|
||||
dictGetOrDefault(dict_name, 'u16', k, toUInt16(42)),
|
||||
dictGetOrDefault(dict_name, 'u32', k, toUInt32(42)),
|
||||
dictGetOrDefault(dict_name, 'u64', k, toUInt64(42));
|
||||
select 'dictGetOrDefault', 'hashed_sparse_ints' as dict_name, toUInt64(0) as k,
|
||||
dictGetOrDefault(dict_name, 'i8', k, toInt8(42)),
|
||||
dictGetOrDefault(dict_name, 'i16', k, toInt16(42)),
|
||||
dictGetOrDefault(dict_name, 'i32', k, toInt32(42)),
|
||||
dictGetOrDefault(dict_name, 'i64', k, toInt64(42)),
|
||||
dictGetOrDefault(dict_name, 'u8', k, toUInt8(42)),
|
||||
dictGetOrDefault(dict_name, 'u16', k, toUInt16(42)),
|
||||
dictGetOrDefault(dict_name, 'u32', k, toUInt32(42)),
|
||||
dictGetOrDefault(dict_name, 'u64', k, toUInt64(42));
|
||||
|
||||
select 'dictGet', 'cache_ints' as dict_name, toUInt64(1) as k,
|
||||
dictGet(dict_name, 'i8', k),
|
||||
dictGet(dict_name, 'i16', k),
|
||||
|
@ -39,6 +39,7 @@ The configuration looks like this:
|
||||
|
||||
- [flat](#flat)
|
||||
- [hashed](#dicts-external_dicts_dict_layout-hashed)
|
||||
- [sparse_hashed](#dicts-external_dicts_dict_layout-sparse_hashed)
|
||||
- [cache](#cache)
|
||||
- [range_hashed](#range-hashed)
|
||||
- [complex_key_hashed](#complex-key-hashed)
|
||||
@ -77,6 +78,18 @@ Configuration example:
|
||||
</layout>
|
||||
```
|
||||
|
||||
### sparse_hashed {#dicts-external_dicts_dict_layout-sparse_hashed}
|
||||
|
||||
Similar to `hashed`, but uses less memory in favor more CPU usage.
|
||||
|
||||
Configuration example:
|
||||
|
||||
```xml
|
||||
<layout>
|
||||
<sparse_hashed />
|
||||
</layout>
|
||||
```
|
||||
|
||||
|
||||
### complex_key_hashed
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user