1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
|
/* Copyright (c) 2019, 2025, Oracle and/or its affiliates.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License, version 2.0,
as published by the Free Software Foundation.
This program is designed to work with certain software (including
but not limited to OpenSSL) that is licensed under separate terms,
as designated in a particular file or component or in included license
documentation. The authors of MySQL hereby grant you an additional
permission to link the program and your derivative works with the
separately licensed software that they have either included with
the program or referenced in the documentation.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License, version 2.0, for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#ifndef SQL_CONSTRAINT_INCLUDED
#define SQL_CONSTRAINT_INCLUDED
#include "my_inttypes.h" // ulonglong
class Alter_constraint_enforcement;
class Alter_drop;
class Alter_info;
class KEY;
struct TABLE;
class THD;
namespace dd {
class Table;
}
/**
Base class to resolve constraints type for the constraints specified in the
ALTER TABLE ... DROP/ALTER CONSTRAINT operation.
For a constraint specified in the DROP/ALTER CONSTRAINT operations of a ALTER
TABLE statement, actual constraint type is unknown. This is the class to
resolve the actual constraint type (PRIMARY, UNIQUE, FOREIGN KEY or CHECK) of
a constraint by name. Changes to Alter_info instance are reverted in the
destructor to make operation safe for re-execution of a stored routines and
prepared statements.
*/
class Constraint_type_resolver {
public:
explicit Constraint_type_resolver(Alter_info *alter_info)
: m_alter_info(alter_info) {}
virtual ~Constraint_type_resolver() = default;
/**
Method to check if constraint type resolution is needed.
@retval true if ALTER TABLE statement has DROP/ALTER CONSTRAINT operations.
@retval false Otherwise.
*/
virtual bool is_type_resolution_needed() const = 0;
/**
Method to resolve constraints type.
@param thd Thread handle.
@param src_table TABLE instance of a source table.
@param dd_src_table Data-dictionary table instance of
a source table.
@retval false Success.
@retval true Failure.
*/
virtual bool resolve_constraints_type(THD *thd, const TABLE *src_table,
const dd::Table *dd_src_table) = 0;
protected:
/**
Helper method to check if "name" type is PRIMARY or UNIQUE constraint.
@param src_table TABLE instance of a source table.
@param name Constraint name.
@retval non-nullptr Returns pointer to KEY instance if "name" is PRIMARY
or UNIQUE constraint.
@retval nullptr Otherwise.
*/
KEY *is_primary_or_unique_constraint(const TABLE *src_table,
const char *name);
/**
Helper method to check if "name" type is REFERENTIAL constraint.
@param dd_src_table Data-dictionary table instance of a source table.
@param name Constraint name.
@retval true If "name" type is REFERENTIAL.
@retval false Otherwise.
*/
bool is_referential_constraint(const dd::Table *dd_src_table,
const char *name);
/**
Helper method to check if "name" type is CHECK constraint.
@param src_table TABLE instance of a source table.
@param name Constraint name.
@retval true If "name" type is CHECK.
@retval false Otherwise.
*/
bool is_check_constraint(const TABLE *src_table, const char *name);
protected:
/// Alter_info instance describing table being altered.
Alter_info *m_alter_info;
};
/**
Class to resolve constraints type for the constraints specified in the
ALTER TABLE ... DROP CONSTRAINT operation.
For a constraint specified in the DROP CONSTRAINT operations of a ALTER TABLE
statement, actual constraint type is unknown. This is the class to resolve
actual constraint type (PRIMARY, UNIQUE, FOREIGN KEY or CHECK) by constraint
name. Alter_drop elements with actual constraint type are added to the
Alter_info::Alter_drop list. To make changes safe for re-execution of a stored
routines and prepared statements, elements added to Alter_drop list are
removed in the destructor.
*/
class Drop_constraint_type_resolver final : public Constraint_type_resolver {
public:
explicit Drop_constraint_type_resolver(Alter_info *alter_info)
: Constraint_type_resolver(alter_info) {}
~Drop_constraint_type_resolver() override;
/**
Method to check if constraint type resolution is needed.
@retval true if ALTER TABLE statement has DROP CONSTRAINT operations.
@retval false Otherwise.
*/
bool is_type_resolution_needed() const override;
/**
Method to resolve constraints type.
@param thd Thread handle.
@param src_table TABLE instance of a source table.
@param dd_src_table Data-dictionary table instance of
a source table.
@retval false Success.
@retval true Failure.
*/
bool resolve_constraints_type(THD *thd, const TABLE *src_table,
const dd::Table *dd_src_table) override;
private:
/**
Method to resolve constraint type.
@param thd Thread handle.
@param src_table TABLE instance of a source table.
@param dd_src_table Data-dictionary table instance of
a source table.
@param drop Alter_drop instance for which
type should be resolved.
@retval false Success.
@retval true Failure.
*/
bool resolve_constraint_type(THD *thd, const TABLE *src_table,
const dd::Table *dd_src_table,
const Alter_drop *drop);
private:
/// Flags set in Alter_info::flags while fixing type for constraint.
ulonglong m_flags{0};
/*
Alter_drop element with actual type is added to the Alter_info::drop_list
for each DROP CONSTRAINT operation. Member holds the position of the first
Alter_drop element with actual type in the Alter_info::drop_list list.
*/
uint m_first_fixed_alter_drop_pos{0};
};
/**
Class to resolve constraints type for the constraints specified in the
ALTER TABLE ... ALTER CONSTRAINT operation.
For a constraint specified in the ALTER CONSTRAINT operations of a ALTER TABLE
statement, actual constraint type is unknown. This is the class to resolve
actual constraint type (PRIMARY, UNIQUE, FOREIGN KEY or CHECK) by constraint
name. Alter_constraint_enforcement elements with actual constraint type are
added to the alter_constraint_enforcement_list. To make changes safe for
re-execution of stored routines and prepared statements, elements added to
list are removed in the destructor.
*/
class Enforce_constraint_type_resolver final : public Constraint_type_resolver {
public:
explicit Enforce_constraint_type_resolver(Alter_info *alter_info)
: Constraint_type_resolver(alter_info) {}
~Enforce_constraint_type_resolver() override;
/**
Method to check if constraint type resolution is needed.
@retval true if ALTER TABLE statement has ALTER CONSTRAINT operations.
@retval false Otherwise.
*/
bool is_type_resolution_needed() const override;
/**
Method to resolve constraints type.
@param thd Thread handle.
@param src_table TABLE instance of a source table.
@param dd_src_table Data-dictionary table instance of
a source table.
@retval false Success.
@retval true Failure.
*/
bool resolve_constraints_type(THD *thd, const TABLE *src_table,
const dd::Table *dd_src_table) override;
private:
/**
Method to resolve constraint type.
@param thd Thread handle.
@param src_table TABLE instance of a source table.
@param dd_src_table Data-dictionary table instance of
a source table.
@param alter_constraint Alter_constraint_enforcement
instance for which type should be
resolved.
@retval false Success.
@retval true Failure.
*/
bool resolve_constraint_type(
THD *thd, const TABLE *src_table, const dd::Table *dd_src_table,
const Alter_constraint_enforcement *alter_constraint);
private:
/// Flags set in Alter_info::flags while fixing type for check constraint.
ulonglong m_flags{0};
/*
Alter_constraint_enforcement element with actual type is added to the
Alter_info::alter_constraint_enforcement_list for each ALTER CONSTRAINT
operation. Member holds position of the first Alter_constraint_enforcement
element with actual type in the alter_constraint_enforcement_list.
*/
uint m_first_fixed_alter_constraint_pos{0};
};
#endif // SQL_CONSTRAINT_INCLUDED
|
