MySQL 8.1.0
Source Code Documentation
opt_statistics.h
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1#ifndef OPT_STATISTICS_INCLUDED
2#define OPT_STATISTICS_INCLUDED
3
4/*
5 Copyright (c) 2014, 2023, Oracle and/or its affiliates.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License, version 2.0,
9 as published by the Free Software Foundation.
10
11 This program is also distributed with certain software (including
12 but not limited to OpenSSL) that is licensed under separate terms,
13 as designated in a particular file or component or in included license
14 documentation. The authors of MySQL hereby grant you an additional
15 permission to link the program and your derivative works with the
16 separately licensed software that they have included with MySQL.
17
18 This program is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License, version 2.0, for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
26
27#include <sys/types.h>
28
29#include "my_inttypes.h" // IWYU pragma: keep
30
31struct TABLE;
32
33typedef float rec_per_key_t;
34class KEY;
35
36/**
37 Guesstimate for "records per key" when index statistics is not available.
38
39 @param table the table
40 @param key the index
41 @param used_keyparts the number of key part that should be included in the
42 estimate
43
44 @return estimated records per key value
45*/
46
47rec_per_key_t guess_rec_per_key(const TABLE *const table, const KEY *const key,
48 uint used_keyparts);
49
50#endif /* OPT_STATISTICS_INCLUDED */
Definition: key.h:112
float rec_per_key_t
Data type for records per key estimates that are stored in the KEY::rec_per_key_float[] array.
Definition: key.h:95
Some integer typedefs for easier portability.
static PFS_engine_table_share_proxy table
Definition: pfs.cc:60
rec_per_key_t guess_rec_per_key(const TABLE *const table, const KEY *const key, uint used_keyparts)
Guesstimate for "records per key" when index statistics is not available.
Definition: opt_statistics.cc:60
float rec_per_key_t
Definition: opt_statistics.h:31
required string key
Definition: replication_asynchronous_connection_failover.proto:59
Definition: table.h:1394