FromTableReordering.h File Reference

#include "InputMetadata.h"
#include "RelAlgExecutionUnit.h"

Include dependency graph for FromTableReordering.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Functions
std::vector< size_t >	get_node_input_permutation (const JoinQualsPerNestingLevel &left_deep_join_quals, const std::vector< InputTableInfo > &table_infos, const Executor *executor)

Function Documentation

std::vector<size_t> get_node_input_permutation	(	const JoinQualsPerNestingLevel &	left_deep_join_quals,
		const std::vector< InputTableInfo > &	table_infos,
		const Executor *	executor
	)

Definition at line 560 of file FromTableReordering.cpp.

References anonymous_namespace{FromTableReordering.cpp}::build_join_cost_graph(), and anonymous_namespace{FromTableReordering.cpp}::traverse_join_cost_graph().

Referenced by anonymous_namespace{RelAlgExecutor.cpp}::do_table_reordering().

                              {
  std::vector<std::map<node_t, InnerQualDecision>> qual_normalization_res(
      table_infos.size());
  const auto join_cost_graph = build_join_cost_graph(
      left_deep_join_quals, table_infos, executor, qual_normalization_res);
  // Use the number of tuples in each table to break ties in BFS.
  const auto compare_node = [&table_infos](const node_t lhs_nest_level,
                                           const node_t rhs_nest_level) {
    return table_infos[lhs_nest_level].info.getNumTuplesUpperBound() <
           table_infos[rhs_nest_level].info.getNumTuplesUpperBound();
  };
  const auto compare_edge = [&compare_node](const TraversalEdge& lhs_edge,
                                            const TraversalEdge& rhs_edge) {
    // Only use the number of tuples as a tie-breaker, if costs are equal.
    if (lhs_edge.join_cost == rhs_edge.join_cost) {
      return compare_node(lhs_edge.nest_level, rhs_edge.nest_level);
    }
    return lhs_edge.join_cost > rhs_edge.join_cost;
  };
  return traverse_join_cost_graph(join_cost_graph,
                                  table_infos,
                                  compare_node,
                                  compare_edge,
                                  left_deep_join_quals,
                                  qual_normalization_res);
}

Here is the call graph for this function:

Here is the caller graph for this function: