MySQL 8.0.31
Source Code Documentation
sql_data_change.h
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1#ifndef SQL_DATA_CHANGE_INCLUDED
2#define SQL_DATA_CHANGE_INCLUDED
3/* Copyright (c) 2000, 2022, Oracle and/or its affiliates.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License, version 2.0,
7 as published by the Free Software Foundation.
8
9 This program is also distributed with certain software (including
10 but not limited to OpenSSL) that is licensed under separate terms,
11 as designated in a particular file or component or in included license
12 documentation. The authors of MySQL hereby grant you an additional
13 permission to link the program and your derivative works with the
14 separately licensed software that they have included with MySQL.
15
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License, version 2.0, for more details.
20
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
24
25/**
26 @file sql_data_change.h
27
28 Contains classes representing SQL-data change statements. The
29 actual implementions of the functionality are found in files
30 sql_{insert, update}.{h,cc}
31*/
32
33#include <assert.h>
34#include <stddef.h>
35#include <sys/types.h>
36
37#include "my_base.h" // ha_rows
38#include "my_bitmap.h" // MY_BITMAP
39
40class Item;
41struct TABLE;
42template <class T>
43class List;
44template <class T>
45class mem_root_deque;
46
48
49/**
50 This class encapsulates a data change operation. There are three such
51 operations.
52
53 -# Insert statements, i.e. INSERT INTO .. VALUES
54
55 -# Update statements. UPDATE @<table@> SET ...
56
57 -# Delete statements. Currently this class is not used for delete statements
58 and thus has not yet been adapted to handle it.
59
60 @todo Rename this class.
61
62 The COPY_INFO structure is used by INSERT/REPLACE code.
63 The schema of the row counting by the INSERT/INSERT ... ON DUPLICATE KEY
64 UPDATE code:
65 If a row is inserted then the copied variable is incremented.
66 If a row is updated by the INSERT ... ON DUPLICATE KEY UPDATE and the
67 new data differs from the old one then the copied and the updated
68 variables are incremented.
69 The touched variable is incremented if a row was touched by the update part
70 of the INSERT ... ON DUPLICATE KEY UPDATE no matter whether the row
71 was actually changed or not.
72*/
73class COPY_INFO {
74 public:
75 class Statistics {
76 public:
78 : records(0),
79 deleted(0),
80 updated(0),
81 copied(0),
82 error_count(0),
83 touched(0) {}
84
85 ha_rows records; /**< Number of processed records */
86 ha_rows deleted; /**< Number of deleted records */
87 ha_rows updated; /**< Number of updated records */
88 ha_rows copied; /**< Number of copied records */
90 ha_rows touched; /* Number of touched records */
91 };
92
94
95 private:
96 COPY_INFO(const COPY_INFO &other); ///< undefined
97 void operator=(COPY_INFO &); ///< undefined
98
99 /// Describes the data change operation that this object represents.
101
102 /**
103 List of columns of the target table which the statement will explicitly
104 fill; and thus we must not set a function default for them.
105 NULL means "empty list".
106 */
108
109 /**
110 A second list of columns like m_changed_columns. See the constructor
111 specific of LOAD DATA INFILE, below.
112 */
114
115 /** Whether this object must manage function defaults */
117 /** Bitmap: bit is set if we should set column number i to its function
118 * default */
120
121 /// Policy for handling insertion of duplicate values.
123
124 protected:
125 /**
126 This function will, unless done already, calculate and keep the set of
127 function default columns.
128
129 Function default columns are those columns declared DEFAULT @<function@>
130 and/or ON UPDATE @<function@>. These will store the return value of
131 @<function@> when the relevant operation is applied on the table.
132
133 Calling this function, without error, is a prerequisite for calling
134 COPY_INFO::set_function_defaults().
135
136 @param table The table to be used for instantiating the column set.
137
138 @retval false Success.
139 @retval true Memory allocation error.
140 */
142
143 /**
144 The column bitmap which has been cached for this data change operation.
145 @see COPY_INFO::get_function_default_columns()
146
147 @return The cached bitmap, or NULL if no bitmap was cached.
148 */
150
151 public:
154 /** Values for UPDATE; needed by write_record() if INSERT with DUP_UPDATE */
156
157 /**
158 Initializes this data change operation as an SQL @c INSERT (with all
159 possible syntaxes and variants).
160
161 @param optype The data change operation type.
162 @param inserted_columns List of columns of the target table which
163 the statement will explicitly fill; COPY_INFO
164 must not set a function default for them. NULL
165 means "empty list".
166 @param manage_defaults Whether this object should manage function
167 defaults.
168 @param duplicate_handling The policy for handling duplicates.
169
170 */
172 bool manage_defaults, enum_duplicates duplicate_handling)
173 : m_optype(optype),
174 m_changed_columns(inserted_columns),
176 m_manage_defaults(manage_defaults),
178 handle_duplicates(duplicate_handling),
179 stats(),
180 escape_char(0),
181 last_errno(0),
183 assert(optype == INSERT_OPERATION);
184 }
185
186 /**
187 Initializes this data change operation as an SQL @c LOAD @c DATA @c
188 INFILE.
189 Note that this statement has its inserted columns spread over two
190 lists:
191@verbatim
192 LOAD DATA INFILE a_file
193 INTO TABLE a_table (col1, col2) < first list (col1, col2)
194 SET col3=val; < second list (col3)
195@endverbatim
196
197 @param optype The data change operation type.
198 @param inserted_columns List of columns of the target table which
199 the statement will explicitly fill; COPY_INFO
200 must not set a function default for them. NULL
201 means "empty list".
202 @param inserted_columns2 A second list like inserted_columns
203 @param manage_defaults Whether this object should manage function
204 defaults.
205 @param duplicates_handling How to handle duplicates.
206 @param escape_character The escape character.
207 */
209 mem_root_deque<Item *> *inserted_columns2, bool manage_defaults,
210 enum_duplicates duplicates_handling, int escape_character)
211 : m_optype(optype),
212 m_changed_columns(inserted_columns),
213 m_changed_columns2(inserted_columns2),
214 m_manage_defaults(manage_defaults),
216 handle_duplicates(duplicates_handling),
217 stats(),
219 last_errno(0),
221 assert(optype == INSERT_OPERATION);
222 }
223
224 /**
225 Initializes this data change operation as an SQL @c UPDATE (multi- or
226 not).
227
228 @param optype The data change operation type.
229 @param fields The column objects that are to be updated.
230 @param values The values to be assigned to the fields.
231 @note that UPDATE always lists columns, so non-listed columns may need a
232 default thus m_manage_defaults is always true.
233 */
236 : m_optype(optype),
237 m_changed_columns(fields),
239 m_manage_defaults(true),
242 stats(),
243 escape_char(0),
244 last_errno(0),
245 update_values(values) {
246 assert(optype == UPDATE_OPERATION);
247 }
248
250
252 return m_changed_columns;
253 }
254
256 return m_changed_columns2;
257 }
258
259 bool get_manage_defaults() const { return m_manage_defaults; }
260
262
263 /**
264 Assigns function default values to columns of the supplied table.
265
266 @note COPY_INFO::get_function_default_columns() and
267 COPY_INFO::add_function_default_columns() must be called prior to invoking
268 this function.
269
270 @param table The table to which columns belong.
271
272 @note It is assumed that all columns in this COPY_INFO are resolved to the
273 table.
274
275 @retval false Success.
276 @retval true Some error happened while executing the default expression.
277 my_error has already been called so the calling function
278 only needs to bail out.
279 */
280 [[nodiscard]] bool set_function_defaults(TABLE *table);
281
282 /**
283 Adds the columns that are bound to receive default values from a function
284 (e.g. CURRENT_TIMESTAMP) to the set columns. Uses lazy instantiation of the
285 set of function default columns.
286
287 @param table The table on which the operation is performed.
288 @param[out] columns The function default columns are added to this set.
289
290 @retval false Success.
291 @retval true Memory allocation error during lazy instantiation.
292 */
294 if (get_function_default_columns(table)) return true;
296 return false;
297 }
298
299 /**
300 True if this operation will set some fields to function default result
301 values when invoked on the table.
302
303 @note COPY_INFO::add_function_default_columns() must be called prior to
304 invoking this function.
305 */
306 bool function_defaults_apply(const TABLE *) const {
307 assert(m_function_default_columns != nullptr);
309 }
310
311 /**
312 True if any of the columns set in the bitmap have default functions
313 that may set the column.
314 */
316 assert(m_function_default_columns != nullptr);
318 }
319
320 /// Reset counters before the next execution
322 stats.records = 0;
323 stats.deleted = 0;
324 stats.updated = 0;
325 stats.copied = 0;
326 stats.error_count = 0;
327 stats.touched = 0;
328 }
329
330 /// Cleanup memory allocated by this object.
332
333 /**
334 Tells the object to not manage function defaults for the last 'count'
335 columns of 'table'.
336 @retval false if success
337 */
338 bool ignore_last_columns(TABLE *table, uint count);
339
340 /**
341 This class allocates its memory in a MEM_ROOT, so there's nothing to
342 delete.
343 */
344 virtual ~COPY_INFO() = default;
345};
346
347#endif // SQL_DATA_CHANGE_INCLUDED
Definition: sql_data_change.h:75
ha_rows deleted
Number of deleted records.
Definition: sql_data_change.h:86
ha_rows records
Number of processed records.
Definition: sql_data_change.h:85
ha_rows copied
Number of copied records.
Definition: sql_data_change.h:88
ha_rows touched
Definition: sql_data_change.h:90
Statistics()
Definition: sql_data_change.h:77
ha_rows error_count
Definition: sql_data_change.h:89
ha_rows updated
Number of updated records.
Definition: sql_data_change.h:87
This class encapsulates a data change operation.
Definition: sql_data_change.h:73
const mem_root_deque< Item * > * get_changed_columns2() const
Definition: sql_data_change.h:255
MY_BITMAP * m_function_default_columns
Bitmap: bit is set if we should set column number i to its function default.
Definition: sql_data_change.h:119
COPY_INFO(const COPY_INFO &other)
undefined
Statistics stats
Definition: sql_data_change.h:152
operation_type
Definition: sql_data_change.h:93
@ UPDATE_OPERATION
Definition: sql_data_change.h:93
@ INSERT_OPERATION
Definition: sql_data_change.h:93
enum enum_duplicates handle_duplicates
Policy for handling insertion of duplicate values.
Definition: sql_data_change.h:122
bool get_function_default_columns(TABLE *table)
This function will, unless done already, calculate and keep the set of function default columns.
Definition: sql_data_change.cc:72
const operation_type m_optype
Describes the data change operation that this object represents.
Definition: sql_data_change.h:100
COPY_INFO(operation_type optype, mem_root_deque< Item * > *fields, mem_root_deque< Item * > *values)
Initializes this data change operation as an SQL UPDATE (multi- or not).
Definition: sql_data_change.h:234
operation_type get_operation_type() const
Definition: sql_data_change.h:249
const bool m_manage_defaults
Whether this object must manage function defaults.
Definition: sql_data_change.h:116
void reset_counters()
Reset counters before the next execution.
Definition: sql_data_change.h:321
MY_BITMAP * get_cached_bitmap() const
The column bitmap which has been cached for this data change operation.
Definition: sql_data_change.h:149
enum_duplicates get_duplicate_handling() const
Definition: sql_data_change.h:261
int escape_char
Definition: sql_data_change.h:153
bool ignore_last_columns(TABLE *table, uint count)
Tells the object to not manage function defaults for the last 'count' columns of 'table'.
Definition: sql_data_change.cc:171
COPY_INFO(operation_type optype, mem_root_deque< Item * > *inserted_columns, mem_root_deque< Item * > *inserted_columns2, bool manage_defaults, enum_duplicates duplicates_handling, int escape_character)
Definition: sql_data_change.h:208
void operator=(COPY_INFO &)
undefined
virtual ~COPY_INFO()=default
This class allocates its memory in a MEM_ROOT, so there's nothing to delete.
mem_root_deque< Item * > * m_changed_columns
List of columns of the target table which the statement will explicitly fill; and thus we must not se...
Definition: sql_data_change.h:107
mem_root_deque< Item * > * m_changed_columns2
A second list of columns like m_changed_columns.
Definition: sql_data_change.h:113
mem_root_deque< Item * > * update_values
Values for UPDATE; needed by write_record() if INSERT with DUP_UPDATE.
Definition: sql_data_change.h:155
COPY_INFO(operation_type optype, mem_root_deque< Item * > *inserted_columns, bool manage_defaults, enum_duplicates duplicate_handling)
Initializes this data change operation as an SQL INSERT (with all possible syntaxes and variants).
Definition: sql_data_change.h:171
int last_errno
Definition: sql_data_change.h:153
bool function_defaults_apply(const TABLE *) const
True if this operation will set some fields to function default result values when invoked on the tab...
Definition: sql_data_change.h:306
void cleanup()
Cleanup memory allocated by this object.
Definition: sql_data_change.h:331
bool add_function_default_columns(TABLE *table, MY_BITMAP *columns)
Adds the columns that are bound to receive default values from a function (e.g.
Definition: sql_data_change.h:293
mem_root_deque< Item * > * get_changed_columns() const
Definition: sql_data_change.h:251
bool function_defaults_apply_on_columns(MY_BITMAP *map)
True if any of the columns set in the bitmap have default functions that may set the column.
Definition: sql_data_change.h:315
bool get_manage_defaults() const
Definition: sql_data_change.h:259
bool set_function_defaults(TABLE *table)
Assigns function default values to columns of the supplied table.
Definition: sql_data_change.cc:131
Base class that is used to represent any kind of expression in a relational query.
Definition: item.h:802
Definition: sql_list.h:433
A (partial) implementation of std::deque allocating its blocks on a MEM_ROOT.
Definition: mem_root_deque.h:109
Fido Client Authentication nullptr
Definition: fido_client_plugin.cc:221
static bool escape_character(char c, String *buf)
Escape a special character in a JSON string, as described in double_quote(), and append it to a buffe...
Definition: json_dom.cc:1103
This file includes constants used by all storage engines.
my_off_t ha_rows
Definition: my_base.h:1139
bool bitmap_is_overlapping(const MY_BITMAP *map1, const MY_BITMAP *map2)
Definition: my_bitmap.cc:300
bool bitmap_is_clear_all(const MY_BITMAP *map)
Definition: my_bitmap.cc:267
void bitmap_union(MY_BITMAP *map, const MY_BITMAP *map2)
Definition: my_bitmap.cc:388
static int count
Definition: myisam_ftdump.cc:42
std::map< Key, Value, Compare, ut::allocator< std::pair< const Key, Value > > > map
Specialization of map which uses ut_allocator.
Definition: ut0new.h:2873
enum_duplicates
Definition: sql_data_change.h:47
@ DUP_REPLACE
Definition: sql_data_change.h:47
@ DUP_UPDATE
Definition: sql_data_change.h:47
@ DUP_ERROR
Definition: sql_data_change.h:47
Definition: my_bitmap.h:42
Definition: table.h:1396
Definition: mysqlslap.cc:237
unsigned int uint
Definition: uca-dump.cc:29