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set @allowed_packet= @@max_allowed_packet;
SET GLOBAL max_allowed_packet=67108864;
connect con1, localhost, root,,;
create table t1(a longblob unique, b longblob , c longblob , unique(b,c));
desc t1;
Field Type Null Key Default Extra
a longblob YES UNI NULL
b longblob YES MUL NULL
c longblob YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` longblob DEFAULT NULL,
`b` longblob DEFAULT NULL,
`c` longblob DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH,
UNIQUE KEY `b` (`b`,`c`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_uca1400_ai_ci
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 Ignored
t1 0 a 1 a A NULL NULL NULL YES HASH NO
t1 0 b 1 b A NULL NULL NULL YES HASH NO
t1 0 b 2 c A NULL NULL NULL YES HASH NO
insert into t1 values(concat(repeat('sachin',10000000),'1'),concat(repeat('sachin',10000000),'1'),
concat(repeat('sachin',10000000),'1'));
insert into t1 values(concat(repeat('sachin',10000000),'2'),concat(repeat('sachin',10000000),'2'),
concat(repeat('sachin',10000000),'1'));
insert into t1 values(concat(repeat('sachin',10000000),'2'),concat(repeat('sachin',10000000),'2'),
concat(repeat('sachin',10000000),'4'));
ERROR 23000: Duplicate entry 'sachinsachinsachinsachinsachinsachinsachinsachinsachinsachins...' for key 'a'
insert into t1 values(concat(repeat('sachin',10000000),'3'),concat(repeat('sachin',10000000),'1'),
concat(repeat('sachin',10000000),'1'));
ERROR 23000: Duplicate entry 'sachinsachinsachinsachinsachinsachinsachinsachinsachinsachins...' for key 'b'
drop table t1;
disconnect con1;
connection default;
set @@GLOBAL.max_allowed_packet= @allowed_packet;
# End of 10.4 tests
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