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
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
|
drop table if exists t1;
drop table if exists t2;
SET SQL_WARNINGS=1;
create table t1 (a int not null auto_increment,b int, primary key (a)) engine=myisam auto_increment=3;
insert into t1 values (1,1),(NULL,3),(NULL,4);
delete from t1 where a=4;
insert into t1 values (NULL,5),(NULL,6);
select * from t1;
a b
1 1
3 3
5 5
6 6
delete from t1 where a=6;
replace t1 values (3,1);
ALTER TABLE t1 add c int;
replace t1 values (3,3,3);
insert into t1 values (NULL,7,7);
update t1 set a=8,b=b+1,c=c+1 where a=7;
insert into t1 values (NULL,9,9);
select * from t1;
a b c
1 1 NULL
3 3 3
5 5 NULL
8 8 8
9 9 9
drop table t1;
create table t1 (
skey tinyint unsigned NOT NULL auto_increment PRIMARY KEY,
sval char(20)
);
insert into t1 values (NULL, "hello");
insert into t1 values (NULL, "hey");
select * from t1;
skey sval
1 hello
2 hey
select _rowid,t1._rowid,skey,sval from t1;
_rowid _rowid skey sval
1 1 1 hello
2 2 2 hey
drop table t1;
create table t1 (a char(10) not null, b int not null auto_increment, primary key(a,b));
insert into t1 values ("a",1),("b",2),("a",2),("c",1);
insert into t1 values ("a",NULL),("b",NULL),("c",NULL),("e",NULL);
insert into t1 (a) values ("a"),("b"),("c"),("d");
insert into t1 (a) values ('k'),('d');
insert into t1 (a) values ("a");
insert into t1 values ("d",last_insert_id());
select * from t1;
a b
a 1
a 2
a 3
a 4
a 5
b 2
b 3
b 4
c 1
c 2
c 3
d 1
d 2
d 5
e 1
k 1
drop table t1;
create table t1 (ordid int(8) not null auto_increment, ord varchar(50) not null, primary key (ordid), index(ord,ordid));
insert into t1 (ordid,ord) values (NULL,'sdj'),(NULL,'sdj');
select * from t1;
ordid ord
1 sdj
2 sdj
drop table t1;
create table t1 (ordid int(8) not null auto_increment, ord varchar(50) not null, primary key (ord,ordid));
insert into t1 values (NULL,'sdj'),(NULL,'sdj'),(NULL,"abc"),(NULL,'abc'),(NULL,'zzz'),(NULL,'sdj'),(NULL,'abc');
select * from t1;
ordid ord
1 abc
2 abc
3 abc
1 sdj
2 sdj
3 sdj
1 zzz
drop table t1;
create table t1 (sid char(5), id int(2) NOT NULL auto_increment, key(sid, id));
create table t2 (sid char(20), id int(2));
insert into t2 values ('skr',NULL),('skr',NULL),('test',NULL);
insert into t1 select * from t2;
select * from t1;
sid id
skr 1
skr 2
test 1
drop table t1,t2;
create table t1 (a int not null primary key auto_increment);
insert into t1 values (0);
update t1 set a=0;
select * from t1;
a
0
check table t1;
Table Op Msg_type Msg_text
test.t1 check warning Found row where the auto_increment column has the value 0
test.t1 check status OK
drop table t1;
create table t1 (a int not null auto_increment primary key);
insert into t1 values (NULL);
insert into t1 values (-1);
select last_insert_id();
last_insert_id()
1
insert into t1 values (NULL);
select * from t1;
a
-1
1
2
drop table t1;
create table t1 (a int not null auto_increment primary key) /*!40102 engine=heap */;
insert into t1 values (NULL);
insert into t1 values (-1);
select last_insert_id();
last_insert_id()
1
insert into t1 values (NULL);
select * from t1;
a
1
-1
2
drop table t1;
create table t1 (i tinyint unsigned not null auto_increment primary key);
insert into t1 set i = 254;
insert into t1 set i = null;
select last_insert_id();
last_insert_id()
255
explain extended select last_insert_id();
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select sql_no_cache last_insert_id() AS `last_insert_id()`
insert into t1 set i = 254;
ERROR 23000: Duplicate entry '254' for key 1
select last_insert_id();
last_insert_id()
255
insert into t1 set i = null;
ERROR 23000: Duplicate entry '255' for key 1
select last_insert_id();
last_insert_id()
0
drop table t1;
create table t1 (i tinyint unsigned not null auto_increment, key (i));
insert into t1 set i = 254;
insert into t1 set i = null;
select last_insert_id();
last_insert_id()
255
insert into t1 set i = null;
Warnings:
Warning 1264 Out of range value adjusted for column 'i' at row 1
select last_insert_id();
last_insert_id()
255
drop table t1;
create table t1 (i tinyint unsigned not null auto_increment primary key, b int, unique (b));
insert into t1 values (NULL, 10);
select last_insert_id();
last_insert_id()
1
insert into t1 values (NULL, 15);
select last_insert_id();
last_insert_id()
2
insert into t1 values (NULL, 10);
ERROR 23000: Duplicate entry '10' for key 2
select last_insert_id();
last_insert_id()
0
drop table t1;
create table t1(a int auto_increment,b int null,primary key(a));
SET SQL_MODE=NO_AUTO_VALUE_ON_ZERO;
insert into t1(a,b)values(NULL,1);
insert into t1(a,b)values(200,2);
insert into t1(a,b)values(0,3);
insert into t1(b)values(4);
insert into t1(b)values(5);
insert into t1(b)values(6);
insert into t1(b)values(7);
select * from t1 order by b;
a b
1 1
200 2
0 3
201 4
202 5
203 6
204 7
alter table t1 modify b mediumint;
select * from t1 order by b;
a b
1 1
200 2
0 3
201 4
202 5
203 6
204 7
create table t2 (a int);
insert t2 values (1),(2);
alter table t2 add b int auto_increment primary key;
select * from t2;
a b
1 1
2 2
drop table t2;
delete from t1 where a=0;
update t1 set a=0 where b=5;
select * from t1 order by b;
a b
1 1
200 2
201 4
0 5
203 6
204 7
delete from t1 where a=0;
update t1 set a=NULL where b=6;
Warnings:
Warning 1263 Column set to default value; NULL supplied to NOT NULL column 'a' at row 4
update t1 set a=300 where b=7;
SET SQL_MODE='';
insert into t1(a,b)values(NULL,8);
insert into t1(a,b)values(400,9);
insert into t1(a,b)values(0,10);
insert into t1(b)values(11);
insert into t1(b)values(12);
insert into t1(b)values(13);
insert into t1(b)values(14);
select * from t1 order by b;
a b
1 1
200 2
201 4
0 6
300 7
301 8
400 9
401 10
402 11
403 12
404 13
405 14
delete from t1 where a=0;
update t1 set a=0 where b=12;
select * from t1 order by b;
a b
1 1
200 2
201 4
300 7
301 8
400 9
401 10
402 11
0 12
404 13
405 14
delete from t1 where a=0;
update t1 set a=NULL where b=13;
Warnings:
Warning 1263 Column set to default value; NULL supplied to NOT NULL column 'a' at row 9
update t1 set a=500 where b=14;
select * from t1 order by b;
a b
1 1
200 2
201 4
300 7
301 8
400 9
401 10
402 11
0 13
500 14
drop table t1;
|
