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|
SET default_storage_engine=InnoDB;
set global innodb_file_per_table=1;
### Test 1 ###
create table worklog5743(a TEXT not null, primary key (a(1000))) ROW_FORMAT=DYNAMIC;
show warnings;
Level Code Message
insert into worklog5743 values(repeat("a", 20000));
update worklog5743 set a = (repeat("b", 16000));
create index idx on worklog5743(a(2000));
show warnings;
Level Code Message
begin;
update worklog5743 set a = (repeat("x", 17000));
select @@session.tx_isolation;
@@session.tx_isolation
REPEATABLE-READ
connect con1,localhost,root,,;
select a = repeat("x", 17000) from worklog5743;
a = repeat("x", 17000)
0
select a = repeat("b", 16000) from worklog5743;
a = repeat("b", 16000)
1
connect con2,localhost,root,,;
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
select @@session.tx_isolation;
@@session.tx_isolation
READ-UNCOMMITTED
select a = repeat("x", 17000) from worklog5743;
a = repeat("x", 17000)
1
connection default;
rollback;
drop table worklog5743;
### Test 2 ###
create table worklog5743(a1 int, a2 TEXT not null) ROW_FORMAT=DYNAMIC;
show warnings;
Level Code Message
create index idx on worklog5743(a1, a2(2000));
show warnings;
Level Code Message
insert into worklog5743 values(9, repeat("a", 10000));
begin;
update worklog5743 set a1 = 1000;
connection con1;
select @@session.tx_isolation;
@@session.tx_isolation
REPEATABLE-READ
explain select a1, a2 = repeat("a", 10000) from worklog5743 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743 ref idx idx 5 const 1
select a1, a2 = repeat("a", 10000) from worklog5743 where a1 = 9;
a1 a2 = repeat("a", 10000)
9 1
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
select @@session.tx_isolation;
@@session.tx_isolation
READ-UNCOMMITTED
select a1, a2 = repeat("a", 10000) from worklog5743 where a1 = 9;
a1 a2 = repeat("a", 10000)
connection default;
rollback;
drop table worklog5743;
### Test 3 ###
create table worklog5743(a1 int, a2 TEXT not null) ROW_FORMAT=DYNAMIC;
create index idx on worklog5743(a1, a2(50));
insert into worklog5743 values(9, repeat("a", 10000));
begin;
update worklog5743 set a1 = 1000;
connection con1;
select @@session.tx_isolation;
@@session.tx_isolation
REPEATABLE-READ
explain select a1, a2 = repeat("a", 10000) from worklog5743 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743 ref idx idx 5 const 1
select a1, a2 = repeat("a", 10000) from worklog5743 where a1 = 9;
a1 a2 = repeat("a", 10000)
9 1
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
select @@session.tx_isolation;
@@session.tx_isolation
READ-UNCOMMITTED
select a1, a2 = repeat("a", 10000) from worklog5743 where a1 = 9;
a1 a2 = repeat("a", 10000)
connection default;
rollback;
drop table worklog5743;
### Test 4 ###
create table worklog5743_1(a1 int, a2 TEXT not null) KEY_BLOCK_SIZE=1;
create table worklog5743_2(a1 int, a2 TEXT not null) KEY_BLOCK_SIZE=2;
create table worklog5743_4(a1 int, a2 TEXT not null) KEY_BLOCK_SIZE=4;
create table worklog5743_8(a1 int, a2 TEXT, a3 TEXT) KEY_BLOCK_SIZE=8;
create table worklog5743_16(a1 int, a2 TEXT, a3 TEXT) KEY_BLOCK_SIZE=16;
set global innodb_large_prefix=0;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx1 on worklog5743_1(a2(4000));
Got one of the listed errors
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 767 bytes
Error 1118 Row size is greater than 900. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
set global innodb_large_prefix=1;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx2 on worklog5743_1(a2(4000));
Got one of the listed errors
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 3072 bytes
Error 1118 Row size is greater than 900. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx3 on worklog5743_1(a2(438));
ERROR 42000: Row size is greater than 900. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Error 1118 Row size is greater than 900. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx4 on worklog5743_1(a2(434));
show warnings;
Level Code Message
create index idx5 on worklog5743_1(a1, a2(432));
ERROR 42000: Row size is greater than 898. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Error 1118 Row size is greater than 898. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx6 on worklog5743_1(a1, a2(428));
show warnings;
Level Code Message
set global innodb_large_prefix=0;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
SET sql_mode= '';
create index idx1 on worklog5743_2(a2(4000));
Warnings:
Note 1071 Specified key was too long; max key length is 767 bytes
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 767 bytes
set global innodb_large_prefix=1;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx2 on worklog5743_2(a2(4000));
ERROR 42000: Row size is greater than 1924. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 3072 bytes
Error 1118 Row size is greater than 1924. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx3 on worklog5743_2(a2(950));
ERROR 42000: Row size is greater than 1924. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Error 1118 Row size is greater than 1924. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx4 on worklog5743_2(a2(946));
show warnings;
Level Code Message
create index idx5 on worklog5743_2(a1, a2(944));
ERROR 42000: Row size is greater than 1922. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Error 1118 Row size is greater than 1922. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx6 on worklog5743_2(a1, a2(940));
show warnings;
Level Code Message
set global innodb_large_prefix=0;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx1 on worklog5743_4(a2(4000));
Warnings:
Note 1071 Specified key was too long; max key length is 767 bytes
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 767 bytes
set global innodb_large_prefix=1;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx2 on worklog5743_4(a2(4000));
ERROR 42000: Row size is greater than 3972. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 3072 bytes
Error 1118 Row size is greater than 3972. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx3 on worklog5743_4(a2(1974));
ERROR 42000: Row size is greater than 3972. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Error 1118 Row size is greater than 3972. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx4 on worklog5743_4(a2(1970));
show warnings;
Level Code Message
create index idx5 on worklog5743_4(a1, a2(1968));
ERROR 42000: Row size is greater than 3970. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
show warnings;
Level Code Message
Error 1118 Row size is greater than 3970. Changing some columns to TEXT or BLOB may help. In current row format, BLOB prefix of 0 bytes is stored inline.
create index idx6 on worklog5743_4(a1, a2(1964));
show warnings;
Level Code Message
set global innodb_large_prefix=0;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx1 on worklog5743_8(a2(1000));
Warnings:
Note 1071 Specified key was too long; max key length is 767 bytes
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 767 bytes
set global innodb_large_prefix=1;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx2 on worklog5743_8(a2(3073));
Warnings:
Note 1071 Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 3072 bytes
create index idx3 on worklog5743_8(a2(3072));
Warnings:
Note 1831 Duplicate index `idx3`. This is deprecated and will be disallowed in a future release
show warnings;
Level Code Message
Note 1831 Duplicate index `idx3`. This is deprecated and will be disallowed in a future release
create index idx4 on worklog5743_8(a1, a2(3069));
ERROR 42000: Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Error 1071 Specified key was too long; max key length is 3072 bytes
create index idx5 on worklog5743_8(a1, a2(3068));
show warnings;
Level Code Message
create index idx6 on worklog5743_8(a1, a2(2000), a3(1069));
ERROR 42000: Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Error 1071 Specified key was too long; max key length is 3072 bytes
create index idx7 on worklog5743_8(a1, a2(2000), a3(1068));
show warnings;
Level Code Message
set global innodb_large_prefix=0;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx1 on worklog5743_16(a2(1000));
Warnings:
Note 1071 Specified key was too long; max key length is 767 bytes
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 767 bytes
set global innodb_large_prefix=1;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
create index idx2 on worklog5743_16(a2(3073));
Warnings:
Note 1071 Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Note 1071 Specified key was too long; max key length is 3072 bytes
create index idx3 on worklog5743_16(a2(3072));
Warnings:
Note 1831 Duplicate index `idx3`. This is deprecated and will be disallowed in a future release
show warnings;
Level Code Message
Note 1831 Duplicate index `idx3`. This is deprecated and will be disallowed in a future release
create index idx4 on worklog5743_16(a1, a2(3069));
ERROR 42000: Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Error 1071 Specified key was too long; max key length is 3072 bytes
create index idx5 on worklog5743_16(a1, a2(3068));
show warnings;
Level Code Message
create index idx6 on worklog5743_16(a1, a2(2000), a3(1069));
ERROR 42000: Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Error 1071 Specified key was too long; max key length is 3072 bytes
create index idx7 on worklog5743_16(a1, a2(2000), a3(1068));
show warnings;
Level Code Message
set sql_mode= default;
insert into worklog5743_1 values(9, repeat("a", 10000));
insert into worklog5743_2 values(9, repeat("a", 10000));
insert into worklog5743_4 values(9, repeat("a", 10000));
insert into worklog5743_8 values(9, repeat("a", 10000), repeat("a", 10000));
insert into worklog5743_16 values(9, repeat("a", 10000), repeat("a", 10000));
set global innodb_large_prefix=0;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
insert into worklog5743_1 values(2, repeat("b", 10000));
insert into worklog5743_2 values(2, repeat("b", 10000));
insert into worklog5743_4 values(2, repeat("b", 10000));
insert into worklog5743_8 values(2, repeat("b", 10000), repeat("b", 10000));
insert into worklog5743_16 values(2, repeat("b", 10000), repeat("b", 10000));
set global innodb_large_prefix=1;
Warnings:
Warning 131 Using innodb_large_prefix is deprecated and the parameter may be removed in future releases. See https://mariadb.com/kb/en/library/xtradbinnodb-file-format/
select a1, left(a2, 20) from worklog5743_1;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
2 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_2;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
2 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_4;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
2 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_8;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
2 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_16;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
2 bbbbbbbbbbbbbbbbbbbb
begin;
update worklog5743_1 set a1 = 1000;
update worklog5743_2 set a1 = 1000;
update worklog5743_4 set a1 = 1000;
update worklog5743_8 set a1 = 1000;
update worklog5743_16 set a1 = 1000;
select a1, left(a2, 20) from worklog5743_1;
a1 left(a2, 20)
1000 aaaaaaaaaaaaaaaaaaaa
1000 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_2;
a1 left(a2, 20)
1000 aaaaaaaaaaaaaaaaaaaa
1000 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_4;
a1 left(a2, 20)
1000 aaaaaaaaaaaaaaaaaaaa
1000 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_8;
a1 left(a2, 20)
1000 aaaaaaaaaaaaaaaaaaaa
1000 bbbbbbbbbbbbbbbbbbbb
select a1, left(a2, 20) from worklog5743_16;
a1 left(a2, 20)
1000 aaaaaaaaaaaaaaaaaaaa
1000 bbbbbbbbbbbbbbbbbbbb
connection con1;
select @@session.tx_isolation;
@@session.tx_isolation
REPEATABLE-READ
explain select a1, left(a2, 20) from worklog5743_1 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743_1 ref idx6 idx6 5 const 1
explain select a1, left(a2, 20) from worklog5743_2 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743_2 ref idx6 idx6 5 const 1
explain select a1, left(a2, 20) from worklog5743_4 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743_4 ref idx6 idx6 5 const 1
explain select a1, left(a2, 20) from worklog5743_8 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743_8 ref idx5,idx7 idx5 5 const 1
explain select a1, left(a2, 20) from worklog5743_16 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743_16 ref idx5,idx7 idx5 5 const 1
select a1, left(a2, 20) from worklog5743_1 where a1 = 9;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
select a1, left(a2, 20) from worklog5743_2 where a1 = 9;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
select a1, left(a2, 20) from worklog5743_4 where a1 = 9;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
select a1, left(a2, 20) from worklog5743_8 where a1 = 9;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
select a1, left(a2, 20) from worklog5743_16 where a1 = 9;
a1 left(a2, 20)
9 aaaaaaaaaaaaaaaaaaaa
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
select @@session.tx_isolation;
@@session.tx_isolation
READ-UNCOMMITTED
select a1, left(a2, 20) from worklog5743_1 where a1 = 9;
a1 left(a2, 20)
select a1, left(a2, 20) from worklog5743_2 where a1 = 9;
a1 left(a2, 20)
select a1, left(a2, 20) from worklog5743_4 where a1 = 9;
a1 left(a2, 20)
select a1, left(a2, 20) from worklog5743_8 where a1 = 9;
a1 left(a2, 20)
select a1, left(a2, 20) from worklog5743_16 where a1 = 9;
a1 left(a2, 20)
connection default;
rollback;
drop table worklog5743_1;
drop table worklog5743_2;
drop table worklog5743_4;
drop table worklog5743_8;
drop table worklog5743_16;
### Test 5 ###
create table worklog5743(a1 int,
a2 varchar(20000),
a3 varchar(3073),
a4 varchar(3072),
a5 varchar(3069),
a6 varchar(3068))
ROW_FORMAT=DYNAMIC;
SET sql_mode='';
create index idx1 on worklog5743(a2);
Warnings:
Warning 1071 Specified key was too long; max key length is 3072 bytes
create index idx2 on worklog5743(a3);
Warnings:
Warning 1071 Specified key was too long; max key length is 3072 bytes
create index idx3 on worklog5743(a4);
show warnings;
Level Code Message
SET sql_mode= default;
create index idx4 on worklog5743(a1, a2);
ERROR 42000: Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Error 1071 Specified key was too long; max key length is 3072 bytes
Error 1071 Specified key was too long; max key length is 3072 bytes
create index idx5 on worklog5743(a1, a5);
ERROR 42000: Specified key was too long; max key length is 3072 bytes
show warnings;
Level Code Message
Error 1071 Specified key was too long; max key length is 3072 bytes
create index idx6 on worklog5743(a1, a6);
show warnings;
Level Code Message
show create table worklog5743;
Table Create Table
worklog5743 CREATE TABLE `worklog5743` (
`a1` int(11) DEFAULT NULL,
`a2` varchar(20000) DEFAULT NULL,
`a3` varchar(3073) DEFAULT NULL,
`a4` varchar(3072) DEFAULT NULL,
`a5` varchar(3069) DEFAULT NULL,
`a6` varchar(3068) DEFAULT NULL,
KEY `idx1` (`a2`(3072)),
KEY `idx2` (`a3`(3072)),
KEY `idx3` (`a4`),
KEY `idx6` (`a1`,`a6`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 ROW_FORMAT=DYNAMIC
insert into worklog5743 values(9,
repeat("a", 20000), repeat("a", 3073),
repeat("a", 3072), repeat("a", 3069),
repeat("a", 3068));
begin;
update worklog5743 set a1 = 1000;
connection con1;
select @@session.tx_isolation;
@@session.tx_isolation
REPEATABLE-READ
explain select a1 from worklog5743 where a1 = 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE worklog5743 ref idx6 idx6 5 const 1 Using index
select a1 from worklog5743 where a1 = 9;
a1
9
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
select @@session.tx_isolation;
@@session.tx_isolation
READ-UNCOMMITTED
select a1 from worklog5743 where a1 = 9;
a1
connection default;
rollback;
drop table worklog5743;
### Test 6 ###
create table worklog5743(a TEXT not null, primary key (a(1000)))
row_format=compact;
ERROR HY000: Index column size too large. The maximum column size is 767 bytes
create table worklog5743(a TEXT)
row_format=compact;
create index idx on worklog5743(a(768));
ERROR HY000: Index column size too large. The maximum column size is 767 bytes
create index idx on worklog5743(a(767));
insert into worklog5743 values(repeat("a", 20000));
begin;
insert into worklog5743 values(repeat("b", 20000));
update worklog5743 set a = (repeat("x", 25000));
select @@session.tx_isolation;
@@session.tx_isolation
REPEATABLE-READ
connection con1;
select a = repeat("a", 20000) from worklog5743;
a = repeat("a", 20000)
1
disconnect con1;
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
select @@session.tx_isolation;
@@session.tx_isolation
READ-UNCOMMITTED
select a = repeat("x", 25000) from worklog5743;
a = repeat("x", 25000)
1
1
disconnect con2;
connection default;
rollback;
drop table worklog5743;
### Test 7 ###
create table worklog5743(a TEXT not null) ROW_FORMAT=DYNAMIC;
SET sql_mode='';
create index idx1 on worklog5743(a(3073));
Warnings:
Note 1071 Specified key was too long; max key length is 3072 bytes
create index idx2 on worklog5743(a(3072));
Warnings:
Note 1831 Duplicate index `idx2`. This is deprecated and will be disallowed in a future release
show create table worklog5743;
Table Create Table
worklog5743 CREATE TABLE `worklog5743` (
`a` text NOT NULL,
KEY `idx1` (`a`(3072)),
KEY `idx2` (`a`(3072))
) ENGINE=InnoDB DEFAULT CHARSET=latin1 ROW_FORMAT=DYNAMIC
drop table worklog5743;
SET sql_mode= default;
create table worklog5743(a TEXT not null) ROW_FORMAT=REDUNDANT;
create index idx on worklog5743(a(768));
ERROR HY000: Index column size too large. The maximum column size is 767 bytes
create index idx2 on worklog5743(a(767));
drop table worklog5743;
create table worklog5743(a TEXT not null) ROW_FORMAT=COMPACT;
create index idx on worklog5743(a(768));
ERROR HY000: Index column size too large. The maximum column size is 767 bytes
create index idx2 on worklog5743(a(767));
drop table worklog5743;
SET GLOBAL innodb_file_per_table=1;
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