113 lines
3.2 KiB
C++
113 lines
3.2 KiB
C++
/*
|
|
* Copyright (C) 2025 Emeric Poupon
|
|
*
|
|
* This file is part of LMS.
|
|
*
|
|
* LMS is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* LMS is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with LMS. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "QueryPlanRecorder.hpp"
|
|
|
|
#include <memory>
|
|
#include <mutex>
|
|
|
|
#include <Wt/Dbo/SqlStatement.h>
|
|
#include <Wt/Dbo/Transaction.h>
|
|
|
|
#include "core/ILogger.hpp"
|
|
|
|
namespace lms::db
|
|
{
|
|
std::unique_ptr<IQueryPlanRecorder> createQueryPlanRecorder()
|
|
{
|
|
return std::make_unique<QueryPlanRecorder>();
|
|
}
|
|
|
|
QueryPlanRecorder::QueryPlanRecorder()
|
|
{
|
|
LMS_LOG(DB, INFO, "Recording database query plans");
|
|
}
|
|
|
|
QueryPlanRecorder::~QueryPlanRecorder() = default;
|
|
|
|
void QueryPlanRecorder::visitQueryPlans(const QueryPlanVisitor& visitor) const
|
|
{
|
|
const std::shared_lock lock{ _mutex };
|
|
|
|
for (const auto& [query, plan] : _queryPlans)
|
|
visitor(query, plan);
|
|
}
|
|
|
|
void QueryPlanRecorder::recordQueryPlanIfNeeded(Wt::Dbo::Session& session, const std::string& query)
|
|
{
|
|
{
|
|
const std::shared_lock lock{ _mutex };
|
|
|
|
if (_queryPlans.contains(query))
|
|
return;
|
|
}
|
|
|
|
Wt::Dbo::Transaction transaction{ session };
|
|
|
|
Wt::Dbo::SqlConnection* connection{ transaction.connection() };
|
|
auto statement{ connection->prepareStatement("EXPLAIN QUERY PLAN " + query) };
|
|
statement->execute();
|
|
|
|
std::map<int, std::string> entries{ { 0, "" } };
|
|
std::map<int, std::vector<int>> relationships;
|
|
|
|
std::string detail;
|
|
while (statement->nextRow())
|
|
{
|
|
detail.clear();
|
|
|
|
int id{};
|
|
int parent{};
|
|
int unused{};
|
|
|
|
if (statement->getResult(0, &id)
|
|
&& statement->getResult(1, &parent)
|
|
&& statement->getResult(2, &unused)
|
|
&& statement->getResult(3, &detail, static_cast<int>(detail.capacity())))
|
|
{
|
|
entries.emplace(id, detail);
|
|
relationships[parent].push_back(id);
|
|
}
|
|
}
|
|
|
|
// format
|
|
std::string result;
|
|
std::function<void(int, unsigned)> formatQuery = [&](int id, unsigned level) -> void {
|
|
for (std::size_t i{}; i < level; ++i)
|
|
result += '\t';
|
|
|
|
result += entries.at(id);
|
|
result += '\n';
|
|
auto itChildren = relationships.find(id);
|
|
if (itChildren == relationships.end())
|
|
return;
|
|
|
|
for (int child : itChildren->second)
|
|
formatQuery(child, level + 1);
|
|
};
|
|
|
|
formatQuery(0, 0);
|
|
|
|
{
|
|
const std::unique_lock lock{ _mutex };
|
|
_queryPlans.try_emplace(query, std::move(result));
|
|
}
|
|
}
|
|
} // namespace lms::db
|