MySQL
8.0.33
Source Code Documentation
node_map.h
Go to the documentation of this file.
1
/* Copyright (c) 2020, 2023, Oracle and/or its affiliates.
2
3
This program is free software; you can redistribute it and/or modify
4
it under the terms of the GNU General Public License, version 2.0,
5
as published by the Free Software Foundation.
6
7
This program is also distributed with certain software (including
8
but not limited to OpenSSL) that is licensed under separate terms,
9
as designated in a particular file or component or in included license
10
documentation. The authors of MySQL hereby grant you an additional
11
permission to link the program and your derivative works with the
12
separately licensed software that they have included with MySQL.
13
14
This program is distributed in the hope that it will be useful,
15
but WITHOUT ANY WARRANTY; without even the implied warranty of
16
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17
GNU General Public License, version 2.0, for more details.
18
19
You should have received a copy of the GNU General Public License
20
along with this program; if not, write to the Free Software
21
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
22
23
#ifndef SQL_JOIN_OPTIMIZER_NODE_MAP_H
24
#define SQL_JOIN_OPTIMIZER_NODE_MAP_H 1
25
26
#include <stdint.h>
27
28
namespace
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
*/
39
using
NodeMap
= uint64_t;
40
41
}
// namespace hypergraph
42
43
#endif
// SQL_JOIN_OPTIMIZER_NODE_MAP_H
hypergraph
Definition:
hypergraph.cc:29
hypergraph::NodeMap
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
sql
join_optimizer
node_map.h
Generated by
1.9.2