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#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 c 1 c A NULL NULL NULL YES BTREE
t1 0 b 1 b 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;
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_2` (`b`,`f`),
UNIQUE KEY `b` (`b`,`c`) USING HASH,
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_2 1 b A NULL NULL NULL YES BTREE
t1 0 b_2 2 f A NULL NULL NULL YES 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 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;
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