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#include <memory>
#include <unordered_map>
#include <vector>
#include "query_optimizer/LogicalToPhysicalMapper.hpp"
#include "query_optimizer/logical/Logical.hpp"
#include "query_optimizer/physical/Physical.hpp"
#include "query_optimizer/strategy/Strategy.hpp"
#include "utility/Macros.hpp"
namespace quickstep {
namespace optimizer {
class OptimizerContext;
/** \addtogroup QueryOptimizer
* @{
* @brief Converts logical plans to physical plans.
class PhysicalGenerator : public LogicalToPhysicalMapper {
* @brief Constructor.
* @param optimizer_context The optimizer context.
explicit PhysicalGenerator(OptimizerContext *optimizer_context)
: optimizer_context_(optimizer_context) {
* @brief Destructor.
~PhysicalGenerator() {}
* @return The generated physical plan.
const physical::PhysicalPtr& physical_plan() const { return physical_plan_; }
* @brief Generates and optimizes a physical plan for \p logical_plan.
* @param logical_plan The logical plan to be converted to a physical plan.
* @return The physical plan.
physical::PhysicalPtr generatePlan(const logical::LogicalPtr &logical_plan);
* @brief Sets the best physical plan for \p logical_plan is \p physical_plan.
* @param logical_plan Logical plan.
* @param physical_plan The physical plan for the logical plan.
void setBestPhysicalForLogical(const logical::LogicalPtr &logical_plan,
const physical::PhysicalPtr &physical_plan);
physical::PhysicalPtr createOrGetPhysicalFromLogical(
const logical::LogicalPtr &logical_plan) final;
* @brief Creates an initial physical plan for \p logical_plan.
* It tries each strategy to the logical plan in order,
* and the physical plan generated by the first strategy that can
* be applied is chosen as the best initial physical plan.
* @param logical_plan The logical plan to be converted to a physical plan.
* @return The initial physical plan.
physical::PhysicalPtr generateInitialPlan(
const logical::LogicalPtr &logical_plan);
* @brief Creates strategies for different types of physical nodes.
void createStrategies();
* @brief Applies physical rules to the initial physical plan.
* @return The optimized physical plan.
physical::PhysicalPtr optimizePlan();
std::vector<std::unique_ptr<strategy::Strategy>> strategies_;
* @brief Maps a logical plan to its initial physical plan.
* We memorize every generated sub-physical plan in this map.
* This map is currently useless, because each logical node is
* visited only once and its physical plan won't be retrieved
* from the map. This is used to allow strategy tests to change
* the plans created for a logical plan by putting intended plans
* into the map so that the generator won't apply a strategy to
* create a plan for a logical node. It also makes testing on
* different strategies to be relatively independent. A strategy test
* only checks one type of physical plans, and manually provides other
* types of physical plans that are not interested. This map will become
* more useful when we have a cost model to evaluate the cost of a
* physical plan. The best physical plan for a logical subplan may be shared
* in multiple physical plans during the plan enumeration.
std::unordered_map<logical::LogicalPtr, physical::PhysicalPtr> logical_to_physical_map_;
OptimizerContext *optimizer_context_;
* @brief The complete physical plan.
physical::PhysicalPtr physical_plan_;
/** @} */
} // namespace optimizer
} // namespace quickstep