MySQL 8.0.29
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node_map.h
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22
23#ifndef SQL_JOIN_OPTIMIZER_NODE_MAP_H
24#define SQL_JOIN_OPTIMIZER_NODE_MAP_H 1
25
26#include <stdint.h>
27
28namespace hypergraph {
29
30/**
31 Since our graphs can never have more than 61 tables, node sets and edge lists
32 are implemented using 64-bit bit sets. This allows for a compact
33 representation and very fast set manipulation; the algorithm does a fair
34 amount of intersections and unions. If we should need extensions to larger
35 graphs later (this will require additional heuristics for reducing the search
36 space), we can use dynamic bit sets, although at a performance cost (we'd
37 probably templatize off the NodeMap type).
38 */
39using NodeMap = uint64_t;
40
41} // namespace hypergraph
42
43#endif // SQL_JOIN_OPTIMIZER_NODE_MAP_H
Definition: hypergraph.cc:30
uint64_t NodeMap
Since our graphs can never have more than 61 tables, node sets and edge lists are implemented using 6...
Definition: node_map.h:39