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|
#Structure of tests
#First we will check all option for
#table containing single unique column
#table containing keys like unique(a,b,c,d) etc
#then table containing 2 blob unique etc
set @allowed_packet= @@max_allowed_packet;
#table with single long blob column;
create table t1(a blob unique );
insert into t1 values(1),(2),(3),(56),('sachin'),('maria'),(123456789034567891),(null),(null),(123456789034567890);
#blob with primary key not allowed
create table t2(a blob,primary key(a(10000)));
ERROR 42000: Specified key was too long; max key length is 1000 bytes
create table t3(a varchar(10000) primary key);
ERROR 42000: Specified key was too long; max key length is 1000 bytes
insert into t1 values(2);
ERROR 23000: Duplicate entry '2' for key 'a'
#table structure;
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
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
MyISAM file: DATADIR/test/t1
Record format: Packed
Character set: latin1_swedish_ci (8)
Data records: 10 Deleted blocks: 0
Recordlength: 12
table description:
Key Start Len Index Type
1 12 8 multip. ulonglong NULL
select TABLE_CATALOG,TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,ORDINAL_POSITION,COLUMN_DEFAULT,IS_NULLABLE,DATA_TYPE,CHARACTER_MAXIMUM_LENGTH,CHARACTER_OCTET_LENGTH,NUMERIC_PRECISION,NUMERIC_SCALE,DATETIME_PRECISION,CHARACTER_SET_NAME,COLLATION_NAME,COLUMN_TYPE,COLUMN_KEY,EXTRA,COLUMN_COMMENT,IS_GENERATED,GENERATION_EXPRESSION from information_schema.columns where table_schema = 'test' and table_name = 't1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE DATETIME_PRECISION CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA COLUMN_COMMENT IS_GENERATED GENERATION_EXPRESSION
def test t1 a 1 NULL YES blob 65535 65535 NULL NULL NULL NULL NULL blob UNI NEVER NULL
select * from information_schema.statistics where table_schema = 'test' and table_name = 't1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT INDEX_COMMENT
def test t1 0 test a 1 a A NULL NULL NULL YES HASH
select * from information_schema.key_column_usage where table_schema= 'test' and table_name= 't1';
CONSTRAINT_CATALOG def
CONSTRAINT_SCHEMA test
CONSTRAINT_NAME a
TABLE_CATALOG def
TABLE_SCHEMA test
TABLE_NAME t1
COLUMN_NAME a
ORDINAL_POSITION 1
POSITION_IN_UNIQUE_CONSTRAINT NULL
REFERENCED_TABLE_SCHEMA NULL
REFERENCED_TABLE_NAME NULL
REFERENCED_COLUMN_NAME NULL
# table select we should not be able to see db_row_hash_column;
select * from t1 order by a;
a
NULL
NULL
1
123456789034567890
123456789034567891
2
3
56
maria
sachin
select db_row_hash_1 from t1;
ERROR 42S22: Unknown column 'db_row_hash_1' in 'field list'
#duplicate entry test;
insert into t1 values(2);
ERROR 23000: Duplicate entry '2' for key 'a'
insert into t1 values('sachin');
ERROR 23000: Duplicate entry 'sachin' for key 'a'
insert into t1 values(123456789034567891);
ERROR 23000: Duplicate entry '123456789034567891' for key 'a'
select * from t1 order by a;
a
NULL
NULL
1
123456789034567890
123456789034567891
2
3
56
maria
sachin
insert into t1 values(11),(22),(33);
insert into t1 values(12),(22);
ERROR 23000: Duplicate entry '22' for key 'a'
select * from t1 order by a;
a
NULL
NULL
1
11
12
123456789034567890
123456789034567891
2
22
3
33
56
maria
sachin
insert into t1 values(repeat('s',4000*10)),(repeat('s',4001*10));
insert into t1 values(repeat('m',4000*10)),(repeat('m',4000*10));
ERROR 23000: Duplicate entry 'mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm...' for key 'a'
insert into t1 values(repeat('m',4001)),(repeat('m',4002));
truncate table t1;
insert into t1 values(1),(2),(3),(4),(5),(8),(7);
MyISAM file: DATADIR/test/t1
Record format: Packed
Character set: latin1_swedish_ci (8)
Data records: 7 Deleted blocks: 0
Recordlength: 12
table description:
Key Start Len Index Type
1 12 8 multip. ulonglong NULL
#now some alter commands;
alter table t1 add column b int;
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
b int(11) YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values(1,2);
ERROR 23000: Duplicate entry '1' for key 'a'
insert into t1 values(2,2);
ERROR 23000: Duplicate entry '2' for key 'a'
select db_row_hash_1 from t1;
ERROR 42S22: Unknown column 'db_row_hash_1' in 'field list'
#now try to change db_row_hash_1 column;
alter table t1 drop column db_row_hash_1;
ERROR 42000: Can't DROP COLUMN `db_row_hash_1`; check that it exists
alter table t1 add column d int , add column e int , drop column db_row_hash_1;
ERROR 42000: Can't DROP COLUMN `db_row_hash_1`; check that it exists
alter table t1 modify column db_row_hash_1 int ;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 add column a int , add column b int, modify column db_row_hash_1 int ;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 change column db_row_hash_1 dsds int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 add column asd int, change column db_row_hash_1 dsds int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 drop column b , add column c int;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`c` int(11) DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
#now add some column with name db_row_hash;
alter table t1 add column db_row_hash_1 int unique;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `a` (`a`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values(45,1,55),(46,1,55);
ERROR 23000: Duplicate entry '55' for key 'db_row_hash_1'
insert into t1 values(45,1,55),(45,1,55);
ERROR 23000: Duplicate entry '45' for key 'a'
alter table t1 add column db_row_hash_2 int, add column db_row_hash_3 int;
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
c int(11) YES NULL
db_row_hash_1 int(11) YES UNI NULL
db_row_hash_2 int(11) YES NULL
db_row_hash_3 int(11) YES NULL
#this should also drop the unique index ;
alter table t1 drop column a;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`)
) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
#add column with unique index on blob ;
alter table t1 add column a blob unique;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
`a` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `a` (`a`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
# try to change the blob unique name;
alter table t1 change column a aa blob ;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
`aa` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `a` (`aa`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 a 1 aa A NULL NULL NULL YES HASH
# try to change the blob unique datatype;
#this will change index to b tree;
alter table t1 modify column aa int ;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
`aa` int(11) DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `a` (`aa`)
) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 a 1 aa A NULL NULL NULL YES BTREE
alter table t1 add column clm blob unique;
#try changing the name ;
alter table t1 change column clm clm_changed blob;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
`aa` int(11) DEFAULT NULL,
`clm_changed` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `a` (`aa`),
UNIQUE KEY `clm` (`clm_changed`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 a 1 aa A NULL NULL NULL YES BTREE
t1 0 clm 1 clm_changed A NULL NULL NULL YES HASH
#now drop the unique key;
alter table t1 drop key clm;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`c` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
`aa` int(11) DEFAULT NULL,
`clm_changed` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `a` (`aa`)
) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 a 1 aa A NULL NULL NULL YES BTREE
drop table t1;
create table t1 (a TEXT CHARSET latin1 COLLATE latin1_german2_ci unique);
desc t1;
Field Type Null Key Default Extra
a text YES UNI NULL
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
insert into t1 values ('ae');
insert into t1 values ('AE');
ERROR 23000: Duplicate entry 'AE' for key 'a'
insert into t1 values ('Ä');
drop table t1;
create table t1 (a int primary key, b blob unique);
desc t1;
Field Type Null Key Default Extra
a int(11) NO PRI NULL
b blob YES UNI NULL
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
insert into t1 values(1,1),(2,2),(3,3);
insert into t1 values(1,1);
ERROR 23000: Duplicate entry '1' for key 'b'
insert into t1 values(7,1);
ERROR 23000: Duplicate entry '1' for key 'b'
drop table t1;
#table with multiple long blob column and varchar text column ;
create table t1(a blob unique, b int , c blob unique , d text unique , e varchar(3000) unique);
insert into t1 values(1,2,3,4,5),(2,11,22,33,44),(3111,222,333,444,555),(5611,2222,3333,4444,5555),
('sachin',341,'fdf','gfgfgfg','hghgr'),('maria',345,'frter','dasd','utyuty'),
(123456789034567891,353534,53453453453456,64565464564564,45435345345345),
(123456789034567890,43545,657567567567,78967657567567,657567567567567676);
#table structure;
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
b int(11) YES NULL
c blob YES UNI NULL
d text YES UNI NULL
e varchar(3000) YES UNI NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH,
UNIQUE KEY `c` (`c`) USING HASH,
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `e` (`e`) 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 a 1 a A NULL NULL NULL YES HASH
t1 0 c 1 c A NULL NULL NULL YES HASH
t1 0 d 1 d A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
MyISAM file: DATADIR/test/t1
Record format: Packed
Character set: latin1_swedish_ci (8)
Data records: 8 Deleted blocks: 0
Recordlength: 3040
table description:
Key Start Len Index Type
1 3039 8 multip. ulonglong NULL
2 3047 8 multip. ulonglong NULL
3 3055 8 multip. ulonglong NULL
4 3063 8 multip. ulonglong NULL
select TABLE_CATALOG,TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,ORDINAL_POSITION,COLUMN_DEFAULT,IS_NULLABLE,DATA_TYPE,CHARACTER_MAXIMUM_LENGTH,CHARACTER_OCTET_LENGTH,NUMERIC_PRECISION,NUMERIC_SCALE,DATETIME_PRECISION,CHARACTER_SET_NAME,COLLATION_NAME,COLUMN_TYPE,COLUMN_KEY,EXTRA,COLUMN_COMMENT,IS_GENERATED,GENERATION_EXPRESSION from information_schema.columns where table_schema = 'test' and table_name = 't1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE DATETIME_PRECISION CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA COLUMN_COMMENT IS_GENERATED GENERATION_EXPRESSION
def test t1 a 1 NULL YES blob 65535 65535 NULL NULL NULL NULL NULL blob UNI NEVER NULL
def test t1 b 2 NULL YES int NULL NULL 10 0 NULL NULL NULL int(11) NEVER NULL
def test t1 c 3 NULL YES blob 65535 65535 NULL NULL NULL NULL NULL blob UNI NEVER NULL
def test t1 d 4 NULL YES text 65535 65535 NULL NULL NULL latin1 latin1_swedish_ci text UNI NEVER NULL
def test t1 e 5 NULL YES varchar 3000 3000 NULL NULL NULL latin1 latin1_swedish_ci varchar(3000) UNI NEVER NULL
select * from information_schema.statistics where table_schema = 'test' and table_name = 't1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT INDEX_COMMENT
def test t1 0 test a 1 a A NULL NULL NULL YES HASH
def test t1 0 test c 1 c A NULL NULL NULL YES HASH
def test t1 0 test d 1 d A NULL NULL NULL YES HASH
def test t1 0 test e 1 e A NULL NULL NULL YES HASH
select * from information_schema.key_column_usage where table_schema= 'test' and table_name= 't1';
CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION POSITION_IN_UNIQUE_CONSTRAINT REFERENCED_TABLE_SCHEMA REFERENCED_TABLE_NAME REFERENCED_COLUMN_NAME
def test a def test t1 a 1 NULL NULL NULL NULL
def test c def test t1 c 1 NULL NULL NULL NULL
def test d def test t1 d 1 NULL NULL NULL NULL
def test e def test t1 e 1 NULL NULL NULL NULL
#table select we should not be able to see db_row_hash_1 column;
select * from t1 order by a;
a b c d e
1 2 3 4 5
123456789034567890 43545 657567567567 78967657567567 657567567567567676
123456789034567891 353534 53453453453456 64565464564564 45435345345345
2 11 22 33 44
3111 222 333 444 555
5611 2222 3333 4444 5555
maria 345 frter dasd utyuty
sachin 341 fdf gfgfgfg hghgr
select db_row_hash_1 from t1;
ERROR 42S22: Unknown column 'db_row_hash_1' in 'field list'
select db_row_hash_2 from t1;
ERROR 42S22: Unknown column 'db_row_hash_2' in 'field list'
select db_row_hash_3 from t1;
ERROR 42S22: Unknown column 'db_row_hash_3' in 'field list'
#duplicate entry test;
insert into t1 values(21,2,3,42,51);
ERROR 23000: Duplicate entry '3' for key 'c'
insert into t1 values('sachin',null,null,null,null);
ERROR 23000: Duplicate entry 'sachin' for key 'a'
insert into t1 values(1234567890345671890,4353451,6575675675617,789676575675617,657567567567567676);
ERROR 23000: Duplicate entry '657567567567567676' for key 'e'
select * from t1 order by a;
a b c d e
1 2 3 4 5
123456789034567890 43545 657567567567 78967657567567 657567567567567676
123456789034567891 353534 53453453453456 64565464564564 45435345345345
2 11 22 33 44
3111 222 333 444 555
5611 2222 3333 4444 5555
maria 345 frter dasd utyuty
sachin 341 fdf gfgfgfg hghgr
insert into t1 values(repeat('s',4000*10),100,repeat('s',4000*10),repeat('s',4000*10),
repeat('s',400)),(repeat('s',4001*10),1000,repeat('s',4001*10),repeat('s',4001*10),
repeat('s',2995));
insert into t1 values(repeat('m',4000*11),10,repeat('s',4000*11),repeat('s',4000*11),repeat('s',2995));
ERROR 23000: Duplicate entry 'sssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss...' for key 'e'
truncate table t1;
insert into t1 values(1,2,3,4,5),(2,11,22,33,44),(3111,222,333,444,555),(5611,2222,3333,4444,5555);
#now some alter commands;
alter table t1 add column f int;
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
b int(11) YES NULL
c blob YES UNI NULL
d text YES UNI NULL
e varchar(3000) YES UNI NULL
f int(11) YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH,
UNIQUE KEY `c` (`c`) USING HASH,
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `e` (`e`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
#unique key should not break;
insert into t1 values(1,2,3,4,5,6);
ERROR 23000: Duplicate entry '1' for key 'a'
select db_row_hash_1 , db_row_hash_2, db_row_hash_3 from t1;
ERROR 42S22: Unknown column 'db_row_hash_1' in 'field list'
#now try to change db_row_hash_1 column;
alter table t1 drop column db_row_hash_1, drop column db_row_hash_2, drop column db_row_hash_3;
ERROR 42000: Can't DROP COLUMN `db_row_hash_1`; check that it exists
alter table t1 add column dg int , add column ef int , drop column db_row_hash_1;
ERROR 42000: Can't DROP COLUMN `db_row_hash_1`; check that it exists
alter table t1 modify column db_row_hash_1 int , modify column db_row_hash_2 int, modify column db_row_hash_3 int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 add column ar int , add column rb int, modify column db_row_hash_1 int , modify column db_row_hash_3 int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 change column db_row_hash_1 dsds int , change column db_row_hash_2 dfdf int , change column db_row_hash_3 gdfg int ;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 add column asd int, drop column a, change column db_row_hash_1 dsds int, change db_row_hash_3 fdfdfd int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 drop column b , add column g int;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH,
UNIQUE KEY `c` (`c`) USING HASH,
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `e` (`e`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
#now add some column with name db_row_hash;
alter table t1 add column db_row_hash_1 int unique;
alter table t1 add column db_row_hash_2 int unique;
alter table t1 add column db_row_hash_3 int unique;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_3` int(11) DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `db_row_hash_2` (`db_row_hash_2`),
UNIQUE KEY `db_row_hash_3` (`db_row_hash_3`),
UNIQUE KEY `a` (`a`) USING HASH,
UNIQUE KEY `c` (`c`) USING HASH,
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `e` (`e`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
alter table t1 add column db_row_hash_7 int, add column db_row_hash_5 int , add column db_row_hash_4 int ;
alter table t1 drop column db_row_hash_7,drop column db_row_hash_3, drop column db_row_hash_4;
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
c blob YES UNI NULL
d text YES UNI NULL
e varchar(3000) YES UNI NULL
f int(11) YES NULL
g int(11) YES NULL
db_row_hash_1 int(11) YES UNI NULL
db_row_hash_2 int(11) YES UNI NULL
db_row_hash_5 int(11) YES NULL
#this should not break anything;
insert into t1 values(1,2,3,4,5,6,23,5,6);
ERROR 23000: Duplicate entry '1' for key 'a'
#this should also drop the unique index;
alter table t1 drop column a, drop column c;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_5` int(11) DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `db_row_hash_2` (`db_row_hash_2`),
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `e` (`e`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 db_row_hash_2 1 db_row_hash_2 A NULL NULL NULL YES BTREE
t1 0 d 1 d A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
#add column with unique index on blob;
alter table t1 add column a blob unique;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_5` int(11) DEFAULT NULL,
`a` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `db_row_hash_2` (`db_row_hash_2`),
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `e` (`e`) USING HASH,
UNIQUE KEY `a` (`a`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 db_row_hash_2 1 db_row_hash_2 A NULL NULL NULL YES BTREE
t1 0 d 1 d A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 a 1 a A NULL NULL NULL YES HASH
#try to change the blob unique column name;
#this will change index to b tree;
alter table t1 modify column a int , modify column e int;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`d` text DEFAULT NULL,
`e` int(11) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_5` int(11) DEFAULT NULL,
`a` int(11) DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `db_row_hash_2` (`db_row_hash_2`),
UNIQUE KEY `e` (`e`),
UNIQUE KEY `a` (`a`),
UNIQUE KEY `d` (`d`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 db_row_hash_2 1 db_row_hash_2 A NULL NULL NULL YES BTREE
t1 0 e 1 e A NULL NULL NULL YES BTREE
t1 0 a 1 a A NULL NULL NULL YES BTREE
t1 0 d 1 d A NULL NULL NULL YES HASH
alter table t1 add column clm1 blob unique,add column clm2 blob unique;
#try changing the name;
alter table t1 change column clm1 clm_changed1 blob, change column clm2 clm_changed2 blob;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`d` text DEFAULT NULL,
`e` int(11) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_5` int(11) DEFAULT NULL,
`a` int(11) DEFAULT NULL,
`clm_changed1` blob DEFAULT NULL,
`clm_changed2` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `db_row_hash_2` (`db_row_hash_2`),
UNIQUE KEY `e` (`e`),
UNIQUE KEY `a` (`a`),
UNIQUE KEY `d` (`d`) USING HASH,
UNIQUE KEY `clm1` (`clm_changed1`) USING HASH,
UNIQUE KEY `clm2` (`clm_changed2`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 db_row_hash_2 1 db_row_hash_2 A NULL NULL NULL YES BTREE
t1 0 e 1 e A NULL NULL NULL YES BTREE
t1 0 a 1 a A NULL NULL NULL YES BTREE
t1 0 d 1 d A NULL NULL NULL YES HASH
t1 0 clm1 1 clm_changed1 A NULL NULL NULL YES HASH
t1 0 clm2 1 clm_changed2 A NULL NULL NULL YES HASH
#now drop the unique key;
alter table t1 drop key clm1, drop key clm2;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`d` text DEFAULT NULL,
`e` int(11) DEFAULT NULL,
`f` int(11) DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
`db_row_hash_5` int(11) DEFAULT NULL,
`a` int(11) DEFAULT NULL,
`clm_changed1` blob DEFAULT NULL,
`clm_changed2` blob DEFAULT NULL,
UNIQUE KEY `db_row_hash_1` (`db_row_hash_1`),
UNIQUE KEY `db_row_hash_2` (`db_row_hash_2`),
UNIQUE KEY `e` (`e`),
UNIQUE KEY `a` (`a`),
UNIQUE KEY `d` (`d`) 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 db_row_hash_1 1 db_row_hash_1 A NULL NULL NULL YES BTREE
t1 0 db_row_hash_2 1 db_row_hash_2 A NULL NULL NULL YES BTREE
t1 0 e 1 e A NULL NULL NULL YES BTREE
t1 0 a 1 a A NULL NULL NULL YES BTREE
t1 0 d 1 d A NULL NULL NULL YES HASH
drop table t1;
#now the table with key on multiple columns; the ultimate test;
create table t1(a blob, b int , c varchar(2000) , d text , e varchar(3000) , f longblob , g int , h text ,
unique(a,b,c), unique(c,d,e),unique(e,f,g,h), unique(b,d,g,h));
insert into t1 values(1,1,1,1,1,1,1,1),(2,2,2,2,2,2,2,2),(3,3,3,3,3,3,3,3),(4,4,4,4,4,4,4,4),(5,5,5,5,5,5,5,5),
('maria',6,'maria','maria','maria','maria',6,'maria'),('mariadb',7,'mariadb','mariadb','mariadb','mariadb',8,'mariadb')
,(null,null,null,null,null,null,null,null),(null,null,null,null,null,null,null,null);
#table structure;
desc t1;
Field Type Null Key Default Extra
a blob YES MUL NULL
b int(11) YES MUL NULL
c varchar(2000) YES MUL NULL
d text YES NULL
e varchar(3000) YES MUL NULL
f longblob YES NULL
g int(11) YES NULL
h text YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
`c` varchar(2000) DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES 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 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
MyISAM file: DATADIR/test/t1
Record format: Packed
Character set: latin1_swedish_ci (8)
Data records: 9 Deleted blocks: 0
Recordlength: 5059
table description:
Key Start Len Index Type
1 5057 8 multip. ulonglong NULL
2 5065 8 multip. ulonglong NULL
3 5073 8 multip. ulonglong NULL
4 5081 8 multip. ulonglong NULL
select TABLE_CATALOG,TABLE_SCHEMA,TABLE_NAME,COLUMN_NAME,ORDINAL_POSITION,COLUMN_DEFAULT,IS_NULLABLE,DATA_TYPE,CHARACTER_MAXIMUM_LENGTH,CHARACTER_OCTET_LENGTH,NUMERIC_PRECISION,NUMERIC_SCALE,DATETIME_PRECISION,CHARACTER_SET_NAME,COLLATION_NAME,COLUMN_TYPE,COLUMN_KEY,EXTRA,COLUMN_COMMENT,IS_GENERATED,GENERATION_EXPRESSION from information_schema.columns where table_schema = 'test' and table_name = 't1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE DATETIME_PRECISION CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA COLUMN_COMMENT IS_GENERATED GENERATION_EXPRESSION
def test t1 a 1 NULL YES blob 65535 65535 NULL NULL NULL NULL NULL blob MUL NEVER NULL
def test t1 b 2 NULL YES int NULL NULL 10 0 NULL NULL NULL int(11) MUL NEVER NULL
def test t1 c 3 NULL YES varchar 2000 2000 NULL NULL NULL latin1 latin1_swedish_ci varchar(2000) MUL NEVER NULL
def test t1 d 4 NULL YES text 65535 65535 NULL NULL NULL latin1 latin1_swedish_ci text NEVER NULL
def test t1 e 5 NULL YES varchar 3000 3000 NULL NULL NULL latin1 latin1_swedish_ci varchar(3000) MUL NEVER NULL
def test t1 f 6 NULL YES longblob 4294967295 4294967295 NULL NULL NULL NULL NULL longblob NEVER NULL
def test t1 g 7 NULL YES int NULL NULL 10 0 NULL NULL NULL int(11) NEVER NULL
def test t1 h 8 NULL YES text 65535 65535 NULL NULL NULL latin1 latin1_swedish_ci text NEVER NULL
select * from information_schema.statistics where table_schema = 'test' and table_name = 't1';
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT INDEX_COMMENT
def test t1 0 test a 1 a A NULL NULL NULL YES HASH
def test t1 0 test a 2 b A NULL NULL NULL YES HASH
def test t1 0 test a 3 c A NULL NULL NULL YES HASH
def test t1 0 test c 1 c A NULL NULL NULL YES HASH
def test t1 0 test c 2 d A NULL NULL NULL YES HASH
def test t1 0 test c 3 e A NULL NULL NULL YES HASH
def test t1 0 test e 1 e A NULL NULL NULL YES HASH
def test t1 0 test e 2 f A NULL NULL NULL YES HASH
def test t1 0 test e 3 g A NULL NULL NULL YES HASH
def test t1 0 test e 4 h A NULL NULL NULL YES HASH
def test t1 0 test b 1 b A NULL NULL NULL YES HASH
def test t1 0 test b 2 d A NULL NULL NULL YES HASH
def test t1 0 test b 3 g A NULL NULL NULL YES HASH
def test t1 0 test b 4 h A NULL NULL NULL YES HASH
select * from information_schema.key_column_usage where table_schema= 'test' and table_name= 't1';
CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION POSITION_IN_UNIQUE_CONSTRAINT REFERENCED_TABLE_SCHEMA REFERENCED_TABLE_NAME REFERENCED_COLUMN_NAME
def test a def test t1 a 1 NULL NULL NULL NULL
def test a def test t1 b 2 NULL NULL NULL NULL
def test a def test t1 c 3 NULL NULL NULL NULL
def test c def test t1 c 1 NULL NULL NULL NULL
def test c def test t1 d 2 NULL NULL NULL NULL
def test c def test t1 e 3 NULL NULL NULL NULL
def test e def test t1 e 1 NULL NULL NULL NULL
def test e def test t1 f 2 NULL NULL NULL NULL
def test e def test t1 g 3 NULL NULL NULL NULL
def test e def test t1 h 4 NULL NULL NULL NULL
def test b def test t1 b 1 NULL NULL NULL NULL
def test b def test t1 d 2 NULL NULL NULL NULL
def test b def test t1 g 3 NULL NULL NULL NULL
def test b def test t1 h 4 NULL NULL NULL NULL
# table select we should not be able to see db_row_hash_1 column;
select * from t1 order by a;
a b c d e f g h
NULL NULL NULL NULL NULL NULL NULL NULL
NULL NULL NULL NULL NULL NULL NULL NULL
1 1 1 1 1 1 1 1
2 2 2 2 2 2 2 2
3 3 3 3 3 3 3 3
4 4 4 4 4 4 4 4
5 5 5 5 5 5 5 5
maria 6 maria maria maria maria 6 maria
mariadb 7 mariadb mariadb mariadb mariadb 8 mariadb
select db_row_hash_1 from t1;
ERROR 42S22: Unknown column 'db_row_hash_1' in 'field list'
select db_row_hash_2 from t1;
ERROR 42S22: Unknown column 'db_row_hash_2' in 'field list'
select db_row_hash_3 from t1;
ERROR 42S22: Unknown column 'db_row_hash_3' in 'field list'
#duplicate entry test;
#duplicate keys entry;
insert into t1 values(1,1,1,0,0,0,0,0);
ERROR 23000: Duplicate entry '1-1-1' for key 'a'
insert into t1 values(0,0,1,1,1,0,0,0);
ERROR 23000: Duplicate entry '1-1-1' for key 'c'
insert into t1 values(0,0,0,0,1,1,1,1);
ERROR 23000: Duplicate entry '1-1-1-1' for key 'e'
insert into t1 values(1,1,1,1,1,0,0,0);
ERROR 23000: Duplicate entry '1-1-1' for key 'a'
insert into t1 values(0,0,0,0,1,1,1,1);
ERROR 23000: Duplicate entry '1-1-1-1' for key 'e'
insert into t1 values(1,1,1,1,1,1,1,1);
ERROR 23000: Duplicate entry '1-1-1' for key 'a'
select db_row_hash_1,db_row_hash_2,db_row_hash_3,db_row_hash_4,db_row_hash_5 from t1;
ERROR 42S22: Unknown column 'db_row_hash_1' in 'field list'
alter table t1 drop column db_row_hash_1, drop column db_row_hash_2, drop column db_row_hash_3;
ERROR 42000: Can't DROP COLUMN `db_row_hash_1`; check that it exists
alter table t1 add column dg int , add column ef int , drop column db_row_hash_1;
ERROR 42000: Can't DROP COLUMN `db_row_hash_1`; check that it exists
alter table t1 modify column db_row_hash_1 int , modify column db_row_hash_2 int, modify column db_row_hash_3 int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 add column ar int , add column rb int, modify column db_row_hash_1 int , modify column db_row_hash_3 int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 change column db_row_hash_1 dsds int , change column db_row_hash_2 dfdf int , change column db_row_hash_3 gdfg int ;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
alter table t1 add column asd int, drop column a, change column db_row_hash_1 dsds int, change db_row_hash_3 fdfdfd int;
ERROR 42S22: Unknown column 'db_row_hash_1' in 't1'
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
`c` varchar(2000) DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
# add column named db_row_hash_*;
alter table t1 add column db_row_hash_7 int , add column db_row_hash_5 int,
add column db_row_hash_1 int, add column db_row_hash_2 int;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
`c` varchar(2000) DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
`db_row_hash_7` int(11) DEFAULT NULL,
`db_row_hash_5` int(11) DEFAULT NULL,
`db_row_hash_1` int(11) DEFAULT NULL,
`db_row_hash_2` int(11) DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES 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 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
alter table t1 drop column db_row_hash_7 , drop column db_row_hash_5 ,
drop column db_row_hash_1, drop column db_row_hash_2 ;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` int(11) DEFAULT NULL,
`c` varchar(2000) DEFAULT NULL,
`d` text DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES 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 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
#try to change column names;
alter table t1 change column a aa blob , change column b bb blob , change column d dd blob;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`aa` blob DEFAULT NULL,
`bb` blob DEFAULT NULL,
`c` varchar(2000) DEFAULT NULL,
`dd` blob DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`aa`,`bb`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`dd`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`bb`,`dd`,`g`,`h`) 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 a 1 aa A NULL NULL NULL YES HASH
t1 0 a 2 bb A NULL NULL NULL YES HASH
t1 0 a 3 c A NULL NULL NULL YES HASH
t1 0 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 dd A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 bb A NULL NULL NULL YES HASH
t1 0 b 2 dd A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
alter table t1 change column aa a blob , change column bb b blob , change column dd d blob;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` blob DEFAULT NULL,
`c` varchar(2000) DEFAULT NULL,
`d` blob DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES 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 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
#now we will change the data type to int and varchar limit so that we no longer require hash_index;
#on key a_b_c;
alter table t1 modify column a varchar(20) , modify column b varchar(20) , modify column c varchar(20);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` varchar(20) DEFAULT NULL,
`b` varchar(20) DEFAULT NULL,
`c` varchar(20) DEFAULT NULL,
`d` blob DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`),
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES BTREE
t1 0 a 2 b A NULL NULL NULL YES BTREE
t1 0 a 3 c A NULL NULL NULL YES BTREE
t1 0 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
#change it back;
alter table t1 modify column a blob , modify column b blob , modify column c blob;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` blob DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` blob DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `c` (`c`,`d`,`e`) USING HASH,
UNIQUE KEY `e` (`e`,`f`,`g`,`h`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES 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 c 1 c A NULL NULL NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
t1 0 c 3 e A NULL NULL NULL YES HASH
t1 0 e 1 e A NULL NULL NULL YES HASH
t1 0 e 2 f A NULL NULL NULL YES HASH
t1 0 e 3 g A NULL NULL NULL YES HASH
t1 0 e 4 h A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
#try to delete blob column in unique;
truncate table t1;
#now try to delete keys;
alter table t1 drop key c, drop key e;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` blob DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` blob DEFAULT NULL,
`e` varchar(3000) DEFAULT NULL,
`f` longblob DEFAULT NULL,
`g` int(11) DEFAULT NULL,
`h` text DEFAULT NULL,
UNIQUE KEY `a` (`a`,`b`,`c`) USING HASH,
UNIQUE KEY `b` (`b`,`d`,`g`,`h`) 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 a 1 a A NULL NULL NULL YES 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 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
t1 0 b 3 g A NULL NULL NULL YES HASH
t1 0 b 4 h A NULL NULL NULL YES HASH
drop table t1;
#now alter table containing some data basically some tests with ignore;
create table t1 (a blob);
insert into t1 values(1),(2),(3);
#normal alter table;
alter table t1 add unique key(a);
alter table t1 drop key a;
truncate table t1;
insert into t1 values(1),(1),(2),(2),(3);
alter table t1 add unique key(a);
ERROR 23000: Duplicate entry '1' for key 'a'
alter ignore table t1 add unique key(a);
select * from t1 order by a;
a
1
2
3
insert into t1 values(1);
ERROR 23000: Duplicate entry '1' for key 'a'
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
UNIQUE KEY `a` (`a`) 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 a 1 a A NULL NULL NULL YES HASH
drop table t1;
#Now with multiple keys;
create table t1(a blob , b blob, c blob , d blob , e int);
insert into t1 values (1,1,1,1,1);
insert into t1 values (1,1,1,1,1);
insert into t1 values (2,1,1,1,1);
insert into t1 values (2,2,2,2,2);
insert into t1 values (3,3,4,4,4);
insert into t1 values (4,4,4,4,4);
alter table t1 add unique key(a,c), add unique key(b,d), add unique key(e);
ERROR 23000: Duplicate entry '1-1' for key 'a'
alter ignore table t1 add unique key(a,c), add unique key(b,d), add unique key(e);
select * from t1 order by a;
a b c d e
1 1 1 1 1
2 2 2 2 2
3 3 4 4 4
insert into t1 values (1,12,1,13,14);
ERROR 23000: Duplicate entry '1-1' for key 'a'
insert into t1 values (12,1,14,1,14);
ERROR 23000: Duplicate entry '1-1' for key 'b'
insert into t1 values (13,12,13,14,4);
ERROR 23000: Duplicate entry '4' for key 'e'
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
`b` blob DEFAULT NULL,
`c` blob DEFAULT NULL,
`d` blob DEFAULT NULL,
`e` int(11) DEFAULT NULL,
UNIQUE KEY `e` (`e`),
UNIQUE KEY `a` (`a`,`c`) USING HASH,
UNIQUE KEY `b` (`b`,`d`) 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 e 1 e A NULL NULL NULL YES BTREE
t1 0 a 1 a A NULL NULL NULL YES HASH
t1 0 a 2 c A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 d A NULL NULL NULL YES HASH
drop table t1;
#visibility of db_row_hash
create table t1 (a blob unique , b blob unique);
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
b blob YES UNI NULL
insert into t1 values(1,19);
insert into t1 values(2,29);
insert into t1 values(3,39);
insert into t1 values(4,49);
create table t2 (DB_ROW_HASH_1 int, DB_ROW_HASH_2 int);
insert into t2 values(11,1);
insert into t2 values(22,2);
insert into t2 values(33,3);
insert into t2 values(44,4);
select * from t1 order by a;
a b
1 19
2 29
3 39
4 49
select * from t2 order by DB_ROW_HASH_1;
DB_ROW_HASH_1 DB_ROW_HASH_2
11 1
22 2
33 3
44 4
select DB_ROW_HASH_1, DB_ROW_HASH_2 from t1;
ERROR 42S22: Unknown column 'DB_ROW_HASH_1' in 'field list'
#bug
select DB_ROW_HASH_1, DB_ROW_HASH_2 from t1,t2;
DB_ROW_HASH_1 DB_ROW_HASH_2
11 1
11 1
11 1
11 1
22 2
22 2
22 2
22 2
33 3
33 3
33 3
33 3
44 4
44 4
44 4
44 4
select * from t1 where DB_ROW_HASH_1 in (select DB_ROW_HASH_1 from t2);
ERROR 42S22: Unknown column 'DB_ROW_HASH_1' in 'IN/ALL/ANY subquery'
select DB_ROW_HASH_1, DB_ROW_HASH_2 from t1,t2 where DB_ROW_HASH_1 in (select DB_ROW_HASH_1 from t2);
DB_ROW_HASH_1 DB_ROW_HASH_2
11 1
22 2
33 3
44 4
11 1
22 2
33 3
44 4
11 1
22 2
33 3
44 4
11 1
22 2
33 3
44 4
select * from t2 where DB_ROW_HASH_1 in (select DB_ROW_HASH_1 from t1);
DB_ROW_HASH_1 DB_ROW_HASH_2
11 1
22 2
33 3
44 4
select DB_ROW_HASH_1 from t1,t2 where t1.DB_ROW_HASH_1 = t2.DB_ROW_HASH_2;
ERROR 42S22: Unknown column 't1.DB_ROW_HASH_1' in 'where clause'
select DB_ROW_HASH_1 from t1 inner join t2 on t1.a = t2.DB_ROW_HASH_2;
DB_ROW_HASH_1
11
22
33
44
drop table t1,t2;
#very long blob entry;
SET @@GLOBAL.max_allowed_packet=67108864;
connect 'newcon', localhost, root,,;
connection newcon;
show variables like 'max_allowed_packet';
Variable_name Value
max_allowed_packet 67108864
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=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 a 1 a A NULL NULL NULL YES HASH
t1 0 b 1 b A NULL NULL NULL YES HASH
t1 0 b 2 c A NULL NULL NULL YES HASH
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;
#long key unique with different key length
create table t1(a blob, unique(a(3000)));
desc t1;
Field Type Null Key Default Extra
a blob YES UNI NULL
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 3000 NULL YES HASH
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
UNIQUE KEY `a` (`a`(3000)) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 value(concat(repeat('s',3000),'1'));
insert into t1 value(concat(repeat('s',3000),'2'));
ERROR 23000: Duplicate entry 'sssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss...' for key 'a'
insert into t1 value(concat(repeat('a',3000),'2'));
drop table t1;
create table t1(a varchar(4000), b longblob , c varchar(5000), d longblob,
unique(a(3500), b), unique(c(4500), d));
desc t1;
Field Type Null Key Default Extra
a varchar(4000) YES MUL NULL
b longblob YES NULL
c varchar(5000) YES MUL NULL
d longblob YES NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` varchar(4000) DEFAULT NULL,
`b` longblob DEFAULT NULL,
`c` varchar(5000) DEFAULT NULL,
`d` longblob DEFAULT NULL,
UNIQUE KEY `a` (`a`(3500),`b`) USING HASH,
UNIQUE KEY `c` (`c`(4500),`d`) 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 a 1 a A NULL 3500 NULL YES HASH
t1 0 a 2 b A NULL NULL NULL YES HASH
t1 0 c 1 c A NULL 4500 NULL YES HASH
t1 0 c 2 d A NULL NULL NULL YES HASH
drop table t1;
disconnect newcon;
connection default;
SET @@GLOBAL.max_allowed_packet=4194304;
#ext bug
create table t1(a int primary key, b blob unique, c int, d blob , index(c));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` int(11) NOT NULL,
`b` blob DEFAULT NULL,
`c` int(11) DEFAULT NULL,
`d` blob DEFAULT NULL,
PRIMARY KEY (`a`),
UNIQUE KEY `b` (`b`) USING HASH,
KEY `c` (`c`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values(1,23,1,33);
insert into t1 values(2,23,1,33);
ERROR 23000: Duplicate entry '23' for key 'b'
drop table t1;
create table t2 (a blob unique , c int , index(c));
show create table t2;
Table Create Table
t2 CREATE TABLE `t2` (
`a` blob DEFAULT NULL,
`c` int(11) DEFAULT NULL,
UNIQUE KEY `a` (`a`) USING HASH,
KEY `c` (`c`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t2 values(1,1);
insert into t2 values(2,1);
drop table t2;
#not null test
create table t1(a blob unique not null);
desc t1;
Field Type Null Key Default Extra
a blob NO UNI NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob NOT NULL,
UNIQUE KEY `a` (`a`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values(1);
insert into t1 values(3);
insert into t1 values(1);
ERROR 23000: Duplicate entry '1' for key 'a'
drop table t1;
create table t1(a int primary key, b blob unique , c blob unique not null);
insert into t1 values(1,1,1);
insert into t1 values(2,1,2);
ERROR 23000: Duplicate entry '1' for key 'b'
insert into t1 values(3,3,1);
ERROR 23000: Duplicate entry '1' for key 'c'
drop table t1;
create table t1 (a blob unique not null, b blob not null, c blob not null, unique(b,c));
desc t1;
Field Type Null Key Default Extra
a blob NO UNI NULL
b blob NO MUL NULL
c blob NO NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob NOT NULL,
`b` blob NOT NULL,
`c` blob NOT NULL,
UNIQUE KEY `a` (`a`) USING HASH,
UNIQUE KEY `b` (`b`,`c`) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values (1, 2, 3);
insert into t1 values (2, 1, 3);
insert into t1 values (2, 1, 3);
ERROR 23000: Duplicate entry '2' for key 'a'
drop table t1;
#partition
create table t1(a blob unique) partition by hash(a);
ERROR HY000: A BLOB field is not allowed in partition function
#key length > 2^16 -1
create table t1(a blob, unique(a(65536)));
ERROR 42000: Specified key part was too long; max key part length is 65535 bytes
create table t1(a blob, unique(a(65535)));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
UNIQUE KEY `a` (`a`(65535)) USING HASH
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
#64 indexes
create table t1 ( a63 blob unique, a62 blob unique, a61 blob unique, a60 blob unique, a59 blob unique, a58 blob unique, a57 blob unique, a56 blob unique, a55 blob unique, a54 blob unique, a53 blob unique, a52 blob unique, a51 blob unique, a50 blob unique, a49 blob unique, a48 blob unique, a47 blob unique, a46 blob unique, a45 blob unique, a44 blob unique, a43 blob unique, a42 blob unique, a41 blob unique, a40 blob unique, a39 blob unique, a38 blob unique, a37 blob unique, a36 blob unique, a35 blob unique, a34 blob unique, a33 blob unique, a32 blob unique, a31 blob unique, a30 blob unique, a29 blob unique, a28 blob unique, a27 blob unique, a26 blob unique, a25 blob unique, a24 blob unique, a23 blob unique, a22 blob unique, a21 blob unique, a20 blob unique, a19 blob unique, a18 blob unique, a17 blob unique, a16 blob unique, a15 blob unique, a14 blob unique, a13 blob unique, a12 blob unique, a11 blob unique, a10 blob unique, a9 blob unique, a8 blob unique, a7 blob unique, a6 blob unique, a5 blob unique, a4 blob unique, a3 blob unique, a2 blob unique, a1 blob unique, a blob unique);;
insert into t1 values( 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0);;
insert into t1 values( 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0);;
ERROR 23000: Duplicate entry '63' for key 'a63'
insert into t1 values( 0, 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);;
insert into t1 values( 0, 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);;
ERROR 23000: Duplicate entry '0' for key 'a63'
drop table t1;
create table t1(a blob , key(a));
Warnings:
Note 1071 Specified key was too long; max key length is 1000 bytes
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
KEY `a` (`a`(1000))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
create table t1(a blob);
alter table t1 add index(a);
Warnings:
Note 1071 Specified key was too long; max key length is 1000 bytes
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` blob DEFAULT NULL,
KEY `a` (`a`(1000))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
create table t1(a text, key(a));
Warnings:
Note 1071 Specified key was too long; max key length is 1000 bytes
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` text DEFAULT NULL,
KEY `a` (`a`(1000))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
create table t1(a varchar(4000));
alter table t1 add index(a);
Warnings:
Warning 1071 Specified key was too long; max key length is 1000 bytes
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` varchar(4000) DEFAULT NULL,
KEY `a` (`a`(1000))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
create table t1 (pk int, a int, b int, primary key(pk), key(pk,a));
alter table t1 modify a text;
ERROR 42000: Specified key was too long; max key length is 1000 bytes
alter table t1 modify a varchar(1000);
ERROR 42000: Specified key was too long; max key length is 1000 bytes
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`pk` int(11) NOT NULL,
`a` int(11) DEFAULT NULL,
`b` int(11) DEFAULT NULL,
PRIMARY KEY (`pk`),
KEY `pk` (`pk`,`a`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
#
# MDEV-19705: Assertion `tmp >= 0' failed in best_access_path
#
CREATE TABLE t1 (d varchar(10)) ENGINE=MyISAM;
INSERT INTO t1 VALUES ('a'),('q');
CREATE TABLE t2 (f varchar(10), a2 datetime, b int, a1 varchar(1024), pk int NOT NULL, PRIMARY KEY (pk), UNIQUE KEY (f,a1,a2), KEY f2 (f(4),a2)) ENGINE=MyISAM;
INSERT INTO t2 VALUES ('aaa','1985-09-06',-163,'s',1),('bbb','1995-01-05',3,'pucaz',2),('ccc','0000-00-00',NULL,'help',3),('ddd',NULL,618,'v',4),('eee','1995-12-20',410,'m',5),('ffq','1976-06-12 20:02:56',NULL,'POKNC',6),('dddd','0000-00-00',-328,'hgsu',7);
explain
SELECT t2.b FROM t1 JOIN t2 ON t1.d = t2.f WHERE t2.pk >= 20;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range PRIMARY,f,f2 PRIMARY 4 NULL 1 Using index condition
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 Using where; Using join buffer (flat, BNL join)
SELECT t2.b FROM t1 JOIN t2 ON t1.d = t2.f WHERE t2.pk >= 20;
b
drop table t1,t2;
#
# MDEV-21470 MyISAM start_bulk_insert doesn't work with long unique
#
CREATE TABLE t1 (a INT, b BLOB) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1,'foo'),(2,'bar');
CREATE TABLE t2 (c BIT, d BLOB, UNIQUE(d)) ENGINE=MyISAM;
INSERT INTO t2 SELECT * FROM t1;
Warnings:
Warning 1264 Out of range value for column 'c' at row 2
DROP TABLE t1, t2;
#
# MDEV-19338 Using AUTO_INCREMENT with long unique
#
CREATE TABLE t1 (pk INT, a TEXT NOT NULL DEFAULT '', PRIMARY KEY (pk), b INT AUTO_INCREMENT, UNIQUE(b), UNIQUE (a,b)) ENGINE=myisam;
ERROR HY000: AUTO_INCREMENT column `b` cannot be used in the UNIQUE index `a`
set @@GLOBAL.max_allowed_packet= @allowed_packet;
|