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
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
|
#structure of tests;
#1 test of table containing single unique blob column;
#2 test of table containing another unique int/ varchar etc column;
#3 test of table containing multiple unique blob column like unique(a),unique(b);
#4 test of table containing multiple multiple unique blob column like unique(a,b...),unique(c,d....);
#structure of each test;
#test if update works;
#test update for duplicate entry;
#test update for no change keys;
#test update for ignore ;
#test 1
create table t1 (a blob unique);
show keys from t1;
Table t1
Non_unique 0
Key_name a
Seq_in_index 1
Column_name a
Collation A
Cardinality NULL
Sub_part NULL
Packed NULL
Null YES
Index_type HASH
Comment
Index_comment
insert into t1 values(1),(2),(3),(4),(5);
select * from t1;
a
1
2
3
4
5
update t1 set a=11 where a=5;
update t1 set a=a+20 where a=1;
select * from t1;
a
21
2
3
4
11
update t1 set a=3 where a=2;
ERROR 23000: Duplicate entry '3' for key 'a'
update t1 set a=4 where a=3;
ERROR 23000: Duplicate entry '4' for key 'a'
#no change in blob key
update t1 set a=3 where a=3;
update t1 set a=2 where a=2;
select* from t1;
a
21
2
3
4
11
#IGNORE;
update ignore t1 set a=3 where a=2;
update ignore t1 set a=4 where a=3;
select * from t1;
a
21
2
3
4
11
drop table t1;
#test 2;
create table t1 (a int primary key, b blob unique , c int unique );
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 PRIMARY 1 a A 0 NULL NULL BTREE
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 c 1 c A NULL NULL NULL YES BTREE
insert into t1 values(1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5),(6,6,6),(7,7,7);
select * from t1 limit 3;
a b c
1 1 1
2 2 2
3 3 3
update t1 set b=34 where a=1;
update t1 set b=a+c+b+34 where b=2;
update t1 set b=a+10+b where c=3;
select * from t1;
a b c
1 34 1
2 40 2
3 16 3
4 4 4
5 5 5
6 6 6
7 7 7
truncate table t1;
insert into t1 values(1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5),(6,6,6),(7,7,7);
update t1 set b=4 where a=3;
ERROR 23000: Duplicate entry '4' for key 'b'
update t1 set b=a+1 where b=3;
ERROR 23000: Duplicate entry '4' for key 'b'
update t1 set b=a+1 where c=3;
ERROR 23000: Duplicate entry '4' for key 'b'
#no change in blob key
update t1 set b=3 where a=3;
update t1 set b=2 where b=2;
update t1 set b=5 where c=5;
select* from t1;
a b c
1 1 1
2 2 2
3 3 3
4 4 4
5 5 5
6 6 6
7 7 7
#IGNORE;
update ignore t1 set b=3 where a=2;
update ignore t1 set b=4 where b=3;
update ignore t1 set b=5 where c=3;
select * from t1;
a b c
1 1 1
2 2 2
3 3 3
4 4 4
5 5 5
6 6 6
7 7 7
drop table t1;
#test 3;
create table t1 (a blob unique, b blob unique , c blob unique);
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 a 1 a A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 c 1 c A NULL NULL NULL YES HASH
insert into t1 values(1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5),(6,6,6),(7,7,7);
select * from t1 limit 3;
a b c
1 1 1
2 2 2
3 3 3
update t1 set b=34 where a=1;
update t1 set b=a+c+b+34 where b=2;
update t1 set b=a+10+b where c=3;
select * from t1;
a b c
1 34 1
2 40 2
3 16 3
4 4 4
5 5 5
6 6 6
7 7 7
truncate table t1;
insert into t1 values(1,1,1),(2,2,2),(3,3,3),(4,4,4),(5,5,5),(6,6,6),(7,7,7);
update t1 set b=4 where a=3;
ERROR 23000: Duplicate entry '4' for key 'b'
update t1 set b=a+1 where b=3;
ERROR 23000: Duplicate entry '4' for key 'b'
update t1 set b=a+1 where c=3;
ERROR 23000: Duplicate entry '4' for key 'b'
#no change in blob key
update t1 set b=3 where a=3;
update t1 set b=2 where b=2;
update t1 set b=5 where c=5;
select* from t1;
a b c
1 1 1
2 2 2
3 3 3
4 4 4
5 5 5
6 6 6
7 7 7
#IGNORE;
update ignore t1 set b=3 where a=2;
update ignore t1 set b=4 where b=3;
update ignore t1 set b=5 where c=3;
update ignore t1 set b=b+3 where a>1 or b>1 or c>1;
select * from t1;
a b c
1 1 1
2 2 2
3 3 3
4 4 4
5 8 5
6 9 6
7 10 7
update ignore t1 set b=b+5 where a>1 and b<5 and c<a+b;
select * from t1;
a b c
1 1 1
2 7 2
3 3 3
4 4 4
5 8 5
6 9 6
7 10 7
drop table t1;
#test 4 ultimate test;
create table t1 (a int primary key , b int, c blob , d blob , e varchar(2000), f int , g text,
unique (b,c), unique (b,f),unique(e,g),unique(a,b,c,d,e,f,g));
desc t1;
Field Type Null Key Default Extra
a int(11) NO PRI NULL
b int(11) YES MUL NULL
c blob YES NULL
d blob YES NULL
e varchar(2000) YES MUL NULL
f int(11) YES NULL
g text YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL,
`b` int(11) DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` blob DEFAULT NULL,
`e` varchar(2000) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` text DEFAULT NULL,
PRIMARY KEY (`a`),
UNIQUE KEY `b` (`b`,`c`) USING HASH,
UNIQUE KEY `b_2` (`b`,`f`),
UNIQUE KEY `e` (`e`,`g`) USING HASH,
UNIQUE KEY `a` (`a`,`b`,`c`,`d`,`e`,`f`,`g`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
show keys from t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 PRIMARY 1 a A 0 NULL NULL BTREE
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 c A NULL NULL NULL YES HASH
t1 0 b_2 1 b A NULL NULL NULL YES BTREE
t1 0 b_2 2 f A NULL NULL NULL YES BTREE
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 g A NULL NULL NULL YES HASH
t1 0 a 1 a A NULL NULL NULL HASH
t1 0 a 2 b A NULL NULL NULL YES HASH
t1 0 a 3 c A NULL NULL NULL YES HASH
t1 0 a 4 d A NULL NULL NULL YES HASH
t1 0 a 5 e A NULL NULL NULL YES HASH
t1 0 a 6 f A NULL NULL NULL YES HASH
t1 0 a 7 g A NULL NULL NULL YES HASH
insert into t1 values(1,1,1,1,1,1,1),(2,2,2,2,2,2,2),(3,3,3,3,3,3,3),(4,4,4,4,4,4,4),
(5,5,5,5,5,5,5),(6,6,6,6,6,6,6),(7,7,7,7,7,7,7),(8,8,8,8,8,8,8),(9,9,9,9,9,9,9);
select * from t1 limit 3;
a b c d e f g
1 1 1 1 1 1 1
2 2 2 2 2 2 2
3 3 3 3 3 3 3
#key b_c
update t1 set b=2 ,c=2 where a=1;
ERROR 23000: Duplicate entry '2-2' for key 'b'
update t1 set b=b+34, c=c+34 where e=1 and g=1 ;
update t1 set b=35, c=35 where e=1 and g=1 ;
update t1 set b=b+1, c=c+1 where a>0;
ERROR 23000: Duplicate entry '3-3' for key 'b'
update ignore t1 set b=b+1, c=c+1 where a>0;
select * from t1 ;
a b c d e f g
1 37 37 1 1 1 1
2 2 2 2 2 2 2
3 3 3 3 3 3 3
4 4 4 4 4 4 4
5 5 5 5 5 5 5
6 6 6 6 6 6 6
7 7 7 7 7 7 7
8 8 8 8 8 8 8
9 10 10 9 9 9 9
truncate table t1;
insert into t1 values(1,1,1,1,1,1,1),(2,2,2,2,2,2,2),(3,3,3,3,3,3,3),(4,4,4,4,4,4,4),
(5,5,5,5,5,5,5),(6,6,6,6,6,6,6),(7,7,7,7,7,7,7),(8,8,8,8,8,8,8),(9,9,9,9,9,9,9);
#key b_f no hash key
update t1 set b=2 , f=2 where a=1;
ERROR 23000: Duplicate entry '2-2' for key 'b_2'
update t1 set b=b+33, f=f+33 where e=1 and g=1;
update t1 set b=34, f=34 where e=1 and g=1 ;
update t1 set b=b+1, f=f+1 where a>0;
ERROR 23000: Duplicate entry '3-3' for key 'b_2'
update ignore t1 set b=b+1, f=f+1 where a>0;
select * from t1 ;
a b c d e f g
1 36 1 1 1 36 1
2 2 2 2 2 2 2
3 3 3 3 3 3 3
4 4 4 4 4 4 4
5 5 5 5 5 5 5
6 6 6 6 6 6 6
7 7 7 7 7 7 7
8 8 8 8 8 8 8
9 10 9 9 9 10 9
truncate table t1;
insert into t1 values(1,1,1,1,1,1,1),(2,2,2,2,2,2,2),(3,3,3,3,3,3,3),(4,4,4,4,4,4,4),
(5,5,5,5,5,5,5),(6,6,6,6,6,6,6),(7,7,7,7,7,7,7),(8,8,8,8,8,8,8),(9,9,9,9,9,9,9);
#key e_g
update t1 set e=2 , g=2 where a=1;
ERROR 23000: Duplicate entry '2-2' for key 'e'
update t1 set e=e+34, g=g+34 where a=1;
update t1 set e=34, g=34 where e=1 and g=1 ;
select * from t1 where a=1;
a b c d e f g
1 1 1 1 35 1 35
update t1 set e=e+1, g=g+1 where a>0;
ERROR 23000: Duplicate entry '3-3' for key 'e'
update ignore t1 set e=e+1, g=g+1 where a>0;
select * from t1 ;
a b c d e f g
1 1 1 1 37 1 37
2 2 2 2 2 2 2
3 3 3 3 3 3 3
4 4 4 4 4 4 4
5 5 5 5 5 5 5
6 6 6 6 6 6 6
7 7 7 7 7 7 7
8 8 8 8 8 8 8
9 9 9 9 10 9 10
drop table t1;
|
