ClickHouse/src/Analyzer/HashUtils.h

62 lines
1.9 KiB
C++
Raw Normal View History

2022-11-17 11:26:39 +00:00
#include <Analyzer/IQueryTreeNode.h>
namespace DB
{
/** This structure holds query tree node ptr and its hash. It can be used as hash map key to avoid unnecessary hash
* recalculations.
*
* Example of usage:
* std::unordered_map<QueryTreeNodeConstRawPtrWithHash, std::string> map;
*/
template <typename QueryTreeNodePtrType>
struct QueryTreeNodeWithHash
{
QueryTreeNodeWithHash(QueryTreeNodePtrType node_) /// NOLINT
: node(std::move(node_))
, hash(node->getTreeHash().first)
{}
QueryTreeNodePtrType node = nullptr;
size_t hash = 0;
};
template <typename T>
inline bool operator==(const QueryTreeNodeWithHash<T> & lhs, const QueryTreeNodeWithHash<T> & rhs)
{
return lhs.hash == rhs.hash && lhs.node->isEqual(*rhs.node);
}
template <typename T>
inline bool operator!=(const QueryTreeNodeWithHash<T> & lhs, const QueryTreeNodeWithHash<T> & rhs)
{
return !(lhs == rhs);
}
using QueryTreeNodePtrWithHash = QueryTreeNodeWithHash<QueryTreeNodePtr>;
using QueryTreeNodeConstPtrWithHash = QueryTreeNodeWithHash<const QueryTreeNodePtr>;
using QueryTreeNodeRawPtrWithHash = QueryTreeNodeWithHash<IQueryTreeNode *>;
using QueryTreeNodeConstRawPtrWithHash = QueryTreeNodeWithHash<const IQueryTreeNode *>;
using QueryTreeNodeConstPtrWithHashSet = std::unordered_set<QueryTreeNodeConstPtrWithHash>;
using QueryTreeNodeConstRawPtrWithHashSet = std::unordered_set<QueryTreeNodeConstRawPtrWithHash>;
template <typename Value>
using QueryTreeNodeConstPtrWithHashMap = std::unordered_map<QueryTreeNodeConstPtrWithHash, Value>;
template <typename Value>
using QueryTreeNodeConstRawPtrWithHashMap = std::unordered_map<QueryTreeNodeConstRawPtrWithHash, Value>;
}
template <typename T>
struct std::hash<DB::QueryTreeNodeWithHash<T>>
{
size_t operator()(const DB::QueryTreeNodeWithHash<T> & node_with_hash) const
{
return node_with_hash.hash;
}
};