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
|
create table t1 (a int, b int, c int, d int, e int);
insert into t1 () values
(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),
(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),
(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),
(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),(),
(),(),(),();
select * into outfile 'load.data' from t1;
create temporary table tmp (a varchar(1024), b int, c int, d int, e linestring, unique (e));
load data infile 'load.data' into table tmp;
delete from tmp;
drop table t1;
create table t1 (b blob) engine=innodb;
alter table t1 add unique (b);
alter table t1 force;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`b` blob DEFAULT NULL,
UNIQUE KEY `b` (`b`) USING HASH
) ENGINE=InnoDB DEFAULT CHARSET=latin1
drop table t1;
create table t1 (pk int, b blob, primary key(pk), unique(b)) engine=myisam;
insert into t1 values (1,'foo');
replace into t1 (pk) values (1);
alter table t1 force;
replace into t1 (pk) values (1);
drop table t1;
create table t1 (t time, unique(t)) engine=innodb;
insert into t1 values (null),(null);
alter ignore table t1 modify t text not null default '';
Warnings:
Warning 1265 Data truncated for column 't' at row 1
Warning 1265 Data truncated for column 't' at row 2
drop table t1;
create table t1 ( pk int, f text, primary key (pk), unique(f)) with system versioning;
insert into t1 values (1,'foo');
update t1 set f = 'bar';
select * from t1;
pk f
1 bar
update t1 set f = 'foo';
select * from t1;
pk f
1 foo
select pk, f, row_end > DATE'2030-01-01' from t1 for system_time all;
pk f row_end > DATE'2030-01-01'
1 foo 1
1 foo 0
1 bar 0
drop table t1;
create temporary table t1 (f blob, unique(f)) engine=innodb;
insert into t1 values (1);
replace into t1 values (1);
drop table t1;
create table t (b blob, unique(b)) engine=myisam;
insert into t values ('foo');
replace into t values ('foo');
drop table t;
CREATE TABLE t1 (f INT, x BLOB, UNIQUE (x));
INSERT INTO t1 VALUES (1,'foo');
ALTER TABLE t1 DROP x, ALGORITHM=INPLACE;
ERROR 0A000: ALGORITHM=INPLACE is not supported for this operation. Try ALGORITHM=COPY
UPDATE t1 SET x = 'bar';
DROP TABLE t1;
create table t1(a blob unique , b blob);
insert into t1 values(1,1),(2,1);
alter table t1 add unique(b);
ERROR 23000: Duplicate entry '1' for key 'b'
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(1,1);
ERROR 23000: Duplicate entry '1' for key 'a'
DROP TABLE t1;
CREATE TABLE t1 (a TEXT, b INT, UNIQUE(a)) ENGINE=MyISAM;
ALTER TABLE t1 DROP x;
ERROR 42000: Can't DROP COLUMN `x`; check that it exists
UPDATE t1 SET b = 0 WHERE a = 'foo';
DROP TABLE t1;
CREATE TABLE t1 (a TEXT, b INT, UNIQUE(a)) ENGINE=InnoDB;
ALTER TABLE t1 DROP x;
ERROR 42000: Can't DROP COLUMN `x`; check that it exists
UPDATE t1 SET b = 0 WHERE a = 'foo';
DROP TABLE t1;
CREATE TEMPORARY TABLE t1 (f BLOB, UNIQUE(f)) ENGINE=InnoDB ROW_FORMAT=COMPACT;
ALTER TABLE t1 ADD KEY (f);
ERROR HY000: Index column size too large. The maximum column size is 767 bytes
TRUNCATE TABLE t1;
SELECT * FROM t1 WHERE f LIKE 'foo';
f
DROP TABLE t1;
CREATE TABLE t1 (a INT, UNIQUE ind USING HASH (a)) ENGINE=InnoDB;
ALTER TABLE t1 CHANGE COLUMN IF EXISTS b a INT;
Warnings:
Note 1054 Unknown column 'b' in 't1'
DROP TABLE t1;
CREATE TABLE t1 (f VARCHAR(4096), UNIQUE(f)) ENGINE=InnoDB;
ALTER TABLE t1 DROP x;
ERROR 42000: Can't DROP COLUMN `x`; check that it exists
SELECT * FROM t1 WHERE f LIKE 'foo';
f
DROP TABLE t1;
CREATE TABLE t1 (pk INT, PRIMARY KEY USING HASH (pk)) ENGINE=InnoDB;
show keys from t1;;
Table t1
Non_unique 0
Key_name PRIMARY
Seq_in_index 1
Column_name pk
Collation A
Cardinality 0
Sub_part NULL
Packed NULL
Null
Index_type BTREE
Comment
Index_comment
ALTER TABLE t1 ADD INDEX (pk);
DROP TABLE t1;
CREATE TABLE t1 (b int, a varchar(4000));
INSERT INTO t1 VALUES (1, 2),(2,3),(3,4);
ALTER TABLE t1 ADD UNIQUE INDEX (a);
SELECT * FROM t1;
b a
1 2
2 3
3 4
SELECT a FROM t1;
a
2
3
4
drop table t1;
CREATE TABLE t1 (f VARCHAR(4096), UNIQUE(f)) ENGINE=InnoDB;
ALTER TABLE t1 DROP KEY f, ADD INDEX idx1(f), ALGORITHM=INSTANT;
ERROR 0A000: ALGORITHM=INSTANT is not supported. Reason: ADD INDEX. Try ALGORITHM=NOCOPY
ALTER TABLE t1 ADD KEY idx2(f);
Warnings:
Warning 1071 Specified key was too long; max key length is 3072 bytes
DROP TABLE t1;
CREATE TABLE t1(a blob , b blob , unique(a,b));
alter table t1 drop column b;
ERROR 42000: Key column 'b' doesn't exist in table
insert into t1 values(1,1);
insert into t1 values(1,1);
ERROR 23000: Duplicate entry '1-1' for key 'a'
alter table t1 add column c int;
drop table t1;
create table t1(a blob , b blob as (a) unique);
insert into t1 values(1, default);
insert into t1 values(1, default);
ERROR 23000: Duplicate entry '1' for key 'b'
drop table t1;
create table t1(a blob, b blob, c blob as (left(a, 5000)) virtual, d blob as (left(b, 5000)) persistent, unique(a,b(4000)));
insert into t1(a,b) values(10,11);
insert into t1(a,b) values(10,11);
ERROR 23000: Duplicate entry '10-11' for key 'a'
insert into t1(a,b) values(2,2);
insert into t1(a,b) values(2,3);
insert into t1(a,b) values(3,2);
drop table t1;
CREATE TABLE t1 (
a CHAR(128),
b CHAR(128) AS (a),
c DATETIME,
UNIQUE(c,b(64))
) ENGINE=InnoDB;
ALTER TABLE t1 MODIFY COLUMN c VARCHAR(4096);
drop table t1;
CREATE TABLE t1 (
a CHAR(128),
b CHAR(128) AS (a),
c varchar(5000),
UNIQUE(c,b(64))
) ENGINE=InnoDB;
drop table t1;
CREATE TABLE t1 (data VARCHAR(4), unique(data) using hash) with system versioning;
INSERT INTO t1 VALUES ('A');
SELECT * INTO OUTFILE 'load.data' from t1;
LOAD DATA INFILE 'load.data' INTO TABLE t1;
ERROR 23000: Duplicate entry 'A' for key 'data'
select * from t1;
data
A
DROP TABLE t1;
CREATE TABLE t1 (data VARCHAR(7961)) ENGINE=InnoDB;
INSERT INTO t1 VALUES ('f'), ('o'), ('o');
SELECT * INTO OUTFILE 'load.data' from t1;
ALTER IGNORE TABLE t1 ADD UNIQUE INDEX (data);
SELECT * FROM t1;
data
f
o
ALTER TABLE t1 ADD SYSTEM VERSIONING ;
SELECT * FROM t1;
data
f
o
REPLACE INTO t1 VALUES ('f'), ('o'), ('o');
SELECT * FROM t1;
data
f
o
LOAD DATA INFILE 'load.data' REPLACE INTO TABLE t1;
SELECT * FROM t1;
data
f
o
DROP TABLE t1;
create table t1 (
c char(10) character set utf8mb4,
unique key a using hash (c(1))
) engine=myisam;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` char(10) CHARACTER SET utf8mb4 DEFAULT NULL,
UNIQUE KEY `a` (`c`(1)) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values ('б');
insert into t1 values ('бб');
ERROR 23000: Duplicate entry 'Ð' for key 'a'
insert into t1 values ('ббб');
ERROR 23000: Duplicate entry 'Ð' for key 'a'
drop table t1;
CREATE TABLE t1 (a INT, UNIQUE USING HASH (a)) PARTITION BY HASH (a) PARTITIONS 2;
INSERT INTO t1 VALUES (2);
REPLACE INTO t1 VALUES (2);
DROP TABLE t1;
set innodb_lock_wait_timeout= 10;
CREATE TABLE t1 (
id int primary key,
f INT unique
) ENGINE=InnoDB;
CREATE TABLE t2 (
id int primary key,
a blob unique
) ENGINE=InnoDB;
START TRANSACTION;
connect con1,localhost,root,,test;
connection con1;
set innodb_lock_wait_timeout= 10;
START TRANSACTION;
INSERT INTO t1 VALUES (1,1)/*1*/;
connection default;
INSERT INTO t2 VALUES (2, 1)/*2*/ ;
connection con1;
INSERT INTO t2 VALUES (3, 1)/*3*/;
connection default;
INSERT IGNORE INTO t1 VALUES (4, 1)/*4*/;
connection con1;
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
disconnect con1;
connection default;
DROP TABLE t1, t2;
|
