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|
drop table if exists t1, t2;
create table t1 (v varchar(30), c char(3), e enum('abc','def','ghi'), t text);
truncate table vchar;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`v` varchar(30) DEFAULT NULL,
`c` char(3) DEFAULT NULL,
`e` enum('abc','def','ghi') DEFAULT NULL,
`t` text
) ENGINE=MyISAM DEFAULT CHARSET=latin1
show create table vchar;
Table Create Table
vchar CREATE TABLE `vchar` (
`v` varchar(30) DEFAULT NULL,
`c` char(3) DEFAULT NULL,
`e` enum('abc','def','ghi') DEFAULT NULL,
`t` text
) ENGINE=MyISAM DEFAULT CHARSET=latin1
insert into t1 values ('abc', 'de', 'ghi', 'jkl');
insert into t1 values ('abc ', 'de ', 'ghi', 'jkl ');
insert into t1 values ('abc ', 'd ', 'ghi', 'jkl ');
insert into vchar values ('abc', 'de', 'ghi', 'jkl');
insert into vchar values ('abc ', 'de ', 'ghi', 'jkl ');
insert into vchar values ('abc ', 'd ', 'ghi', 'jkl ');
select length(v),length(c),length(e),length(t) from t1;
length(v) length(c) length(e) length(t)
3 2 3 3
4 2 3 4
7 1 3 7
select length(v),length(c),length(e),length(t) from vchar;
length(v) length(c) length(e) length(t)
3 2 3 3
3 2 3 4
3 1 3 7
alter table vchar add i int;
show create table vchar;
Table Create Table
vchar CREATE TABLE `vchar` (
`v` varchar(30) DEFAULT NULL,
`c` char(3) DEFAULT NULL,
`e` enum('abc','def','ghi') DEFAULT NULL,
`t` text,
`i` int(11) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1
select length(v),length(c),length(e),length(t) from vchar;
length(v) length(c) length(e) length(t)
3 2 3 3
3 2 3 4
3 1 3 7
drop table t1, vchar;
create table t1 (v varchar(20));
insert into t1 values('a ');
select v='a' from t1;
v='a'
1
select binary v='a' from t1;
binary v='a'
0
select binary v='a ' from t1;
binary v='a '
1
insert into t1 values('a');
alter table t1 add primary key (v);
ERROR 23000: Duplicate entry 'a' for key 'PRIMARY'
drop table t1;
create table t1 (v varbinary(20));
insert into t1 values('a');
insert into t1 values('a ');
alter table t1 add primary key (v);
drop table t1;
create table t1 (v varchar(254), index (v));
insert into t1 values ("This is a test ");
insert into t1 values ("Some sample data");
insert into t1 values (" garbage ");
insert into t1 values (" This is a test ");
insert into t1 values ("This is a test");
insert into t1 values ("Hello world");
insert into t1 values ("Foo bar");
insert into t1 values ("This is a test");
insert into t1 values ("MySQL varchar test");
insert into t1 values ("test MySQL varchar");
insert into t1 values ("This is a long string to have some random length data included");
insert into t1 values ("Short string");
insert into t1 values ("VSS");
insert into t1 values ("Some samples");
insert into t1 values ("Bar foo");
insert into t1 values ("Bye");
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 257 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 257 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 257 NULL 2 Using where; Using index
alter table t1 change v v varchar(255);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 258 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 258 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 258 NULL 2 Using where; Using index
alter table t1 change v v varchar(256);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 259 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 259 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 259 NULL 2 Using where; Using index
alter table t1 change v v varchar(257);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 260 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 260 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 260 NULL 2 Using where; Using index
alter table t1 change v v varchar(258);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 261 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 261 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 261 NULL 2 Using where; Using index
alter table t1 change v v varchar(259);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 262 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 262 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 262 NULL 2 Using where; Using index
alter table t1 change v v varchar(258);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 261 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 261 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 261 NULL 2 Using where; Using index
alter table t1 change v v varchar(257);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 260 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 260 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 260 NULL 2 Using where; Using index
alter table t1 change v v varchar(256);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 259 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 259 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 259 NULL 2 Using where; Using index
alter table t1 change v v varchar(255);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 258 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 258 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 258 NULL 2 Using where; Using index
alter table t1 change v v varchar(254);
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 257 NULL 3 Using where; Using index
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 257 const 3 Using where; Using index
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 257 NULL 2 Using where; Using index
alter table t1 change v v varchar(253);
alter table t1 change v v varchar(254), drop key v;
alter table t1 change v v varchar(300), add key (v(10));
select * from t1 where v like 'This is a test' order by v;
v
This is a test
This is a test
select * from t1 where v='This is a test' order by v;
v
This is a test
This is a test
This is a test
select * from t1 where v like 'S%' order by v;
v
Short string
Some sample data
Some samples
explain select * from t1 where v like 'This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 13 NULL 4 Using where; Using filesort
explain select * from t1 where v='This is a test' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref v v 13 const 4 Using where
explain select * from t1 where v like 'S%' order by v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v v 13 NULL 2 Using where; Using filesort
drop table t1;
create table t1 (pkcol varchar(16), othercol varchar(16), primary key (pkcol));
insert into t1 values ('test', 'something');
update t1 set othercol='somethingelse' where pkcol='test';
select * from t1;
pkcol othercol
test somethingelse
drop table t1;
create table t1 (a int, b varchar(12));
insert into t1 values (1, 'A'), (22, NULL);
create table t2 (a int);
insert into t2 values (22), (22);
select t1.a, t1.b, min(t1.b) from t1 inner join t2 ON t2.a = t1.a
group by t1.b, t1.a;
a b min(t1.b)
22 NULL NULL
drop table t1, t2;
create table t1 (f1 varchar(65500));
create index index1 on t1(f1(10));
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` varchar(65500) DEFAULT NULL,
KEY `index1` (`f1`(10))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
alter table t1 modify f1 varchar(255);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` varchar(255) DEFAULT NULL,
KEY `index1` (`f1`(10))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
alter table t1 modify f1 tinytext;
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`f1` tinytext,
KEY `index1` (`f1`(10))
) ENGINE=MyISAM DEFAULT CHARSET=latin1
drop table t1;
DROP TABLE IF EXISTS t1;
CREATE TABLE t1(f1 VARCHAR(100) DEFAULT 'test');
INSERT INTO t1 VALUES(SUBSTR(f1, 1, 3));
DROP TABLE IF EXISTS t1;
CREATE TABLE t1(f1 CHAR(100) DEFAULT 'test');
INSERT INTO t1 VALUES(SUBSTR(f1, 1, 3));
DROP TABLE IF EXISTS t1;
drop table if exists t1, t2, t3;
create table t3 (
id int(11),
en varchar(255) character set utf8,
cz varchar(255) character set utf8
);
truncate table t3;
insert into t3 (id, en, cz) values
(1,'en string 1','cz string 1'),
(2,'en string 2','cz string 2'),
(3,'en string 3','cz string 3');
create table t1 (
id int(11),
name_id int(11)
);
insert into t1 (id, name_id) values (1,1), (2,3), (3,3);
create table t2 (id int(11));
insert into t2 (id) values (1), (2), (3);
select t1.*, t2.id, t3.en, t3.cz from t1 left join t2 on t1.id=t2.id
left join t3 on t1.id=t3.id order by t3.id;
Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr
def test t1 t1 id id 3 11 1 Y 32768 0 63
def test t1 t1 name_id name_id 3 11 1 Y 32768 0 63
def test t2 t2 id id 3 11 1 Y 32768 0 63
def test t3 t3 en en 253 255 11 Y 0 0 8
def test t3 t3 cz cz 253 255 11 Y 0 0 8
id name_id id en cz
1 1 1 en string 1 cz string 1
2 3 2 en string 2 cz string 2
3 3 3 en string 3 cz string 3
drop table t1, t2, t3;
CREATE TABLE t1 (a CHAR(2));
INSERT INTO t1 VALUES (10), (50), (30), ('1a'), (60), ('t');
SELECT a,(a + 0) FROM t1 ORDER BY a;
a (a + 0)
10 10
1a 1
30 30
50 50
60 60
t 0
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: '1a'
Warning 1292 Truncated incorrect DOUBLE value: 't '
SELECT a,(a DIV 2) FROM t1 ORDER BY a;
a (a DIV 2)
10 5
1a 0
30 15
50 25
60 30
t 0
Warnings:
Warning 1292 Truncated incorrect DECIMAL value: '1a'
Warning 1918 Encountered illegal value '' when converting to DECIMAL
Warning 1292 Truncated incorrect DECIMAL value: 't '
SELECT a,CAST(a AS SIGNED) FROM t1 ORDER BY a;
a CAST(a AS SIGNED)
10 10
1a 1
30 30
50 50
60 60
t 0
Warnings:
Warning 1292 Truncated incorrect INTEGER value: '1a'
Warning 1292 Truncated incorrect INTEGER value: 't'
DROP TABLE t1;
CREATE TABLE t1 (a VARCHAR(16));
INSERT INTO t1 VALUES ('5'), ('s'), ('');
SELECT 5 = a FROM t1;
5 = a
1
0
0
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: 's'
DROP TABLE t1;
CREATE TABLE t1 (a CHAR(16));
INSERT INTO t1 VALUES ('5'), ('s'), ('');
SELECT 5 = a FROM t1;
5 = a
1
0
0
Warnings:
Warning 1292 Truncated incorrect DOUBLE value: 's '
DROP TABLE t1;
#
# Start of 10.0 tests
#
#
# MDEV-6950 Bad results with joins comparing DATE and INT/ENUM/VARCHAR columns
#
CREATE TABLE t1 (c1 DATE PRIMARY KEY);
INSERT INTO t1 VALUES ('2001-01-01');
CREATE TABLE t2 (c1 VARCHAR(20));
INSERT INTO t2 VALUES ('2001-01-01');
INSERT INTO t2 VALUES ('2001/01/01');
SELECT t1.* FROM t1,t2 WHERE t1.c1=t2.c1;
c1
2001-01-01
2001-01-01
SELECT t1.* FROM t1 LEFT JOIN t2 ON t1.c1=t2.c1;
c1
2001-01-01
2001-01-01
ALTER TABLE t2 ADD PRIMARY KEY(c1);
SELECT t1.* FROM t1,t2 WHERE t1.c1=t2.c1;
c1
2001-01-01
2001-01-01
EXPLAIN SELECT t1.* FROM t1,t2 WHERE t1.c1=t2.c1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system PRIMARY NULL NULL NULL 1
1 SIMPLE t2 index PRIMARY PRIMARY 22 NULL 2 Using where; Using index
SELECT t1.* FROM t1 LEFT JOIN t2 ON t1.c1=t2.c1;
c1
2001-01-01
2001-01-01
# t2 should NOT be eliminated
EXPLAIN SELECT t1.* FROM t1 LEFT JOIN t2 ON t1.c1=t2.c1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1
1 SIMPLE t2 index PRIMARY PRIMARY 22 NULL 2 Using where; Using index
DROP TABLE IF EXISTS t1,t2;
#
# MDEV-6989 BINARY and COLLATE xxx_bin comparisions are not used for optimization in some cases
#
CREATE TABLE t1 (c1 VARCHAR(20) CHARACTER SET latin1, PRIMARY KEY(c1));
INSERT INTO t1 VALUES ('a'),('b'),('c'),('d');
SELECT * FROM t1 WHERE c1=BINARY 'a';
c1
a
EXPLAIN SELECT * FROM t1 WHERE c1=BINARY 'a';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 22 const 1 Using index
SELECT * FROM t1 WHERE c1=_latin1'a' COLLATE latin1_bin;
c1
a
EXPLAIN SELECT * FROM t1 WHERE c1=_latin1'a' COLLATE latin1_bin;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 22 const 1 Using index
DROP TABLE t1;
CREATE TABLE t1 (c1 VARCHAR(10) CHARACTER SET latin1 COLLATE latin1_bin);
INSERT INTO t1 VALUES ('a');
CREATE TABLE t2 (c1 VARCHAR(10) CHARACTER SET latin1, PRIMARY KEY(c1));
INSERT INTO t2 VALUES ('a'),('b');
SELECT * FROM t1, t2 WHERE t1.c1=t2.c1;
c1 c1
a a
EXPLAIN SELECT * FROM t1, t2 WHERE t1.c1=t2.c1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1
1 SIMPLE t2 const PRIMARY PRIMARY 12 const 1 Using index
ALTER TABLE t1 MODIFY c1 VARBINARY(10);
SELECT * FROM t1, t2 WHERE t1.c1=t2.c1;
c1 c1
a a
EXPLAIN SELECT * FROM t1, t2 WHERE t1.c1=t2.c1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system NULL NULL NULL NULL 1
1 SIMPLE t2 const PRIMARY PRIMARY 12 const 1 Using index
DROP TABLE t1, t2;
CREATE TABLE t1 (c1 VARCHAR(10) CHARACTER SET latin1 COLLATE latin1_bin);
INSERT INTO t1 VALUES ('a'),('c');
CREATE TABLE t2 (c1 VARCHAR(10) CHARACTER SET latin1, PRIMARY KEY(c1));
INSERT INTO t2 VALUES ('a'),('b');
SELECT t1.* FROM t1 LEFT JOIN t2 USING (c1);
c1
a
c
# t2 should be eliminated
EXPLAIN SELECT t1.* FROM t1 LEFT JOIN t2 USING (c1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
ALTER TABLE t1 MODIFY c1 VARBINARY(10);
SELECT t1.* FROM t1 LEFT JOIN t2 USING (c1);
c1
a
c
# t2 should be eliminated
EXPLAIN SELECT t1.* FROM t1 LEFT JOIN t2 USING (c1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
DROP TABLE t1,t2;
#
# End of 10.0 tests
#
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