MySQL 8.4.0
Source Code Documentation
table_session_variables.h
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23
24#ifndef TABLE_SESSION_VARIABLES_H
25#define TABLE_SESSION_VARIABLES_H
26
27/**
28 @file storage/perfschema/table_session_variables.h
29 Table SESSION_VARIABLES (declarations).
30*/
31
32#include <sys/types.h>
33
34#include "my_base.h"
35#include "my_inttypes.h"
40
41class Field;
42class Plugin_table;
43struct TABLE;
44struct THR_LOCK;
45/**
46 @addtogroup performance_schema_tables
47 @{
48*/
49
51 public:
53 : PFS_engine_index(&m_key), m_key("VARIABLE_NAME") {}
54
55 ~PFS_index_session_variables() override = default;
56
57 virtual bool match(const System_variable *pfs);
58
59 private:
61};
62
63/**
64 A row of table
65 PERFORMANCE_SCHEMA.SESSION_VARIABLES.
66*/
68 /** Column VARIABLE_NAME. */
70 /** Column VARIABLE_VALUE. */
72};
73
74/** Table PERFORMANCE_SCHEMA.SESSION_VARIABLES. */
77
78 public:
79 /** Table share */
82 static ha_rows get_row_count();
83
84 void reset_position() override;
85
86 int rnd_init(bool scan) override;
87 int rnd_next() override;
88 int rnd_pos(const void *pos) override;
89
90 int index_init(uint idx, bool sorted) override;
91 int index_next() override;
92
93 protected:
94 int read_row_values(TABLE *table, unsigned char *buf, Field **fields,
95 bool read_all) override;
97
98 public:
99 ~table_session_variables() override = default;
100
101 protected:
102 int make_row(const System_variable *system_var);
103
104 private:
105 /** Table share lock. */
107 /** Table definition. */
109
110 /** Current THD variables. */
112 /** Current row. */
114 /** Current position. */
116 /** Next position. */
118
120};
121
122/** @} */
123#endif
Definition: field.h:575
Definition: pfs_engine_table.h:300
An abstract PERFORMANCE_SCHEMA table.
Definition: pfs_engine_table.h:70
Definition: table_session_variables.h:50
virtual bool match(const System_variable *pfs)
Definition: table_session_variables.cc:47
PFS_key_variable_name m_key
Definition: table_session_variables.h:60
PFS_index_session_variables()
Definition: table_session_variables.h:52
~PFS_index_session_variables() override=default
Definition: table_helper.h:1577
System variable cache.
Definition: pfs_variable.h:606
Class to hold information regarding a table to be created on behalf of a plugin.
Definition: plugin_table.h:40
System variable derived from sys_var object.
Definition: pfs_variable.h:169
Table PERFORMANCE_SCHEMA.SESSION_VARIABLES.
Definition: table_session_variables.h:75
PFS_simple_index pos_t
Definition: table_session_variables.h:76
static PFS_engine_table_share m_share
Table share.
Definition: table_session_variables.h:80
static ha_rows get_row_count()
Definition: table_session_variables.cc:92
pos_t m_pos
Current position.
Definition: table_session_variables.h:115
PFS_index_session_variables * m_opened_index
Definition: table_session_variables.h:119
int rnd_init(bool scan) override
Initialize table scan.
Definition: table_session_variables.cc:116
pos_t m_next_pos
Next position.
Definition: table_session_variables.h:117
~table_session_variables() override=default
row_session_variables m_row
Current row.
Definition: table_session_variables.h:113
int index_next() override
Find key in index, read record.
Definition: table_session_variables.cc:167
static Plugin_table m_table_def
Table definition.
Definition: table_session_variables.h:108
int make_row(const System_variable *system_var)
Definition: table_session_variables.cc:186
int rnd_pos(const void *pos) override
Fetch a row by position.
Definition: table_session_variables.cc:139
int index_init(uint idx, bool sorted) override
Definition: table_session_variables.cc:152
int rnd_next() override
Fetch the next row in this cursor.
Definition: table_session_variables.cc:123
table_session_variables()
Definition: table_session_variables.cc:105
static THR_LOCK m_table_lock
Table share lock.
Definition: table_session_variables.h:106
PFS_system_variable_cache m_sysvar_cache
Current THD variables.
Definition: table_session_variables.h:111
static PFS_engine_table * create(PFS_engine_table_share *)
Definition: table_session_variables.cc:88
int read_row_values(TABLE *table, unsigned char *buf, Field **fields, bool read_all) override
Read the current row values.
Definition: table_session_variables.cc:199
void reset_position() override
Reset the cursor position to the beginning of the table.
Definition: table_session_variables.cc:111
This file includes constants used by all storage engines.
my_off_t ha_rows
Definition: my_base.h:1141
Some integer typedefs for easier portability.
static PFS_engine_table_share_proxy table
Definition: pfs.cc:61
Definition: buf0block_hint.cc:30
Performance schema tables (declarations).
Performance schema system and status variables (declarations).
static const LEX_CSTRING pfs
Definition: sql_show_processlist.cc:66
Performance schema instrumentation (declarations).
A PERFORMANCE_SCHEMA table share.
Definition: pfs_engine_table.h:358
Position of a cursor, for simple iterations.
Definition: pfs_engine_table.h:558
Definition: table_helper.h:1115
Definition: table_helper.h:1128
Definition: table.h:1405
Definition: thr_lock.h:139
A row of table PERFORMANCE_SCHEMA.SESSION_VARIABLES.
Definition: table_session_variables.h:67
PFS_variable_name_row m_variable_name
Column VARIABLE_NAME.
Definition: table_session_variables.h:69
PFS_variable_value_row m_variable_value
Column VARIABLE_VALUE.
Definition: table_session_variables.h:71
Helpers to implement a performance schema table.