mirror of
https://github.com/MariaDB/server.git
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969 lines
27 KiB
Text
969 lines
27 KiB
Text
create table t1(a int not null, b int, c char(10) not null, d varchar(20)) engine = innodb;
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insert into t1 values (5,5,'oo','oo'),(4,4,'tr','tr'),(3,4,'ad','ad'),(2,3,'ak','ak');
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commit;
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alter table t1 add index b (b), add index b (b);
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ERROR 42000: Duplicate key name 'b'
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alter table t1 add index (b,b);
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ERROR 42S21: Duplicate column name 'b'
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alter table t1 add index d2 (d);
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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KEY `d2` (`d`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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explain select * from t1 force index(d2) order by d;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL d2 23 NULL 4
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select * from t1 force index (d2) order by d;
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a b c d
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3 4 ad ad
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2 3 ak ak
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5 5 oo oo
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4 4 tr tr
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alter table t1 add unique index (b);
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ERROR 23000: Duplicate entry '4' for key 'b'
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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KEY `d2` (`d`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t1 add index (b);
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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KEY `d2` (`d`),
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KEY `b` (`b`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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CREATE TABLE `t1#1`(a INT PRIMARY KEY) ENGINE=InnoDB;
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alter table t1 add unique index (c), add index (d);
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ERROR HY000: Table 'test.t1#1' already exists
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rename table `t1#1` to `t1#2`;
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alter table t1 add unique index (c), add index (d);
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ERROR HY000: Table 'test.t1#2' already exists
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drop table `t1#2`;
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alter table t1 add unique index (c), add index (d);
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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UNIQUE KEY `c` (`c`),
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KEY `d2` (`d`),
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KEY `b` (`b`),
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KEY `d` (`d`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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explain select * from t1 force index(c) order by c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL c 10 NULL 4
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drop index c on t1;
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ERROR 42000: This table type requires a primary key
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alter table t1 add primary key (a), drop index c;
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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KEY `d2` (`d`),
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KEY `b` (`b`),
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KEY `d` (`d`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t1 add primary key (c);
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ERROR 42000: Multiple primary key defined
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alter table t1 drop primary key, add primary key (b);
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ERROR 23000: Duplicate entry '4' for key 'PRIMARY'
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create unique index c on t1 (c);
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `c` (`c`),
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KEY `d2` (`d`),
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KEY `b` (`b`),
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KEY `d` (`d`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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explain select * from t1 force index(c) order by c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL c 10 NULL 4
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select * from t1 force index(c) order by c;
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a b c d
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3 4 ad ad
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2 3 ak ak
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5 5 oo oo
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4 4 tr tr
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alter table t1 drop index b, add index (b);
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `c` (`c`),
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KEY `d2` (`d`),
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KEY `d` (`d`),
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KEY `b` (`b`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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insert into t1 values(6,1,'ggg','ggg');
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select * from t1;
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a b c d
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2 3 ak ak
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3 4 ad ad
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4 4 tr tr
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5 5 oo oo
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6 1 ggg ggg
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select * from t1 force index(b) order by b;
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a b c d
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6 1 ggg ggg
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2 3 ak ak
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3 4 ad ad
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4 4 tr tr
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5 5 oo oo
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select * from t1 force index(c) order by c;
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a b c d
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3 4 ad ad
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2 3 ak ak
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6 1 ggg ggg
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5 5 oo oo
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4 4 tr tr
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select * from t1 force index(d) order by d;
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a b c d
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3 4 ad ad
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2 3 ak ak
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6 1 ggg ggg
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5 5 oo oo
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4 4 tr tr
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explain select * from t1 force index(b) order by b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL b 5 NULL 5
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explain select * from t1 force index(c) order by c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL c 10 NULL 5
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explain select * from t1 force index(d) order by d;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL d 23 NULL 5
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) NOT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `c` (`c`),
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KEY `d2` (`d`),
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KEY `d` (`d`),
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KEY `b` (`b`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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drop table t1;
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create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a)) engine = innodb;
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insert into t1 values (1,1,'ab','ab'),(2,2,'ac','ac'),(3,3,'ad','ad'),(4,4,'afe','afe');
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commit;
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alter table t1 add index (c(2));
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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KEY `c` (`c`(2))
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t1 add unique index (d(10));
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `d` (`d`(10)),
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KEY `c` (`c`(2))
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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insert into t1 values(5,1,'ggg','ggg');
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select * from t1;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 3 ad ad
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4 4 afe afe
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5 1 ggg ggg
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select * from t1 force index(c) order by c;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 3 ad ad
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4 4 afe afe
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5 1 ggg ggg
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select * from t1 force index(d) order by d;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 3 ad ad
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4 4 afe afe
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5 1 ggg ggg
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explain select * from t1 order by b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 5 Using filesort
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explain select * from t1 force index(c) order by c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 5 Using filesort
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explain select * from t1 force index(d) order by d;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 5 Using filesort
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `d` (`d`(10)),
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KEY `c` (`c`(2))
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t1 drop index d;
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insert into t1 values(8,9,'fff','fff');
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select * from t1;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 3 ad ad
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4 4 afe afe
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5 1 ggg ggg
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8 9 fff fff
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select * from t1 force index(c) order by c;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 3 ad ad
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4 4 afe afe
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8 9 fff fff
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5 1 ggg ggg
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explain select * from t1 order by b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using filesort
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explain select * from t1 force index(c) order by c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using filesort
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explain select * from t1 order by d;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using filesort
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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KEY `c` (`c`(2))
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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drop table t1;
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create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a)) engine = innodb;
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insert into t1 values (1,1,'ab','ab'),(2,2,'ac','ac'),(3,2,'ad','ad'),(4,4,'afe','afe');
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commit;
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alter table t1 add unique index (b,c);
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insert into t1 values(8,9,'fff','fff');
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select * from t1;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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select * from t1 force index(b) order by b;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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explain select * from t1 force index(b) order by b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL b 16 NULL 5
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `b` (`b`,`c`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t1 add index (b,c);
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insert into t1 values(11,11,'kkk','kkk');
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select * from t1;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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11 11 kkk kkk
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select * from t1 force index(b) order by b;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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11 11 kkk kkk
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explain select * from t1 force index(b) order by b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL b 16 NULL 6
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `b` (`b`,`c`),
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KEY `b_2` (`b`,`c`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t1 add unique index (c,d);
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insert into t1 values(13,13,'yyy','aaa');
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select * from t1;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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11 11 kkk kkk
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13 13 yyy aaa
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select * from t1 force index(b) order by b;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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11 11 kkk kkk
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13 13 yyy aaa
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select * from t1 force index(c) order by c;
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a b c d
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1 1 ab ab
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2 2 ac ac
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3 2 ad ad
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4 4 afe afe
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8 9 fff fff
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11 11 kkk kkk
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13 13 yyy aaa
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explain select * from t1 force index(b) order by b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL b 16 NULL 7
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explain select * from t1 force index(c) order by c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL c 34 NULL 7
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show create table t1;
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Table Create Table
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t1 CREATE TABLE `t1` (
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`a` int(11) NOT NULL,
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`b` int(11) DEFAULT NULL,
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`c` char(10) DEFAULT NULL,
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`d` varchar(20) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `b` (`b`,`c`),
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UNIQUE KEY `c` (`c`,`d`),
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KEY `b_2` (`b`,`c`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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drop table t1;
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create table t1(a int not null, b int not null, c int, primary key (a), key (b)) engine = innodb;
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create table t3(a int not null, c int not null, d int, primary key (a), key (c)) engine = innodb;
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create table t4(a int not null, d int not null, e int, primary key (a), key (d)) engine = innodb;
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create table t2(a int not null, b int not null, c int not null, d int not null, e int,
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foreign key (b) references t1(b) on delete cascade,
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foreign key (c) references t3(c), foreign key (d) references t4(d))
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engine = innodb;
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alter table t1 drop index b;
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ERROR HY000: Cannot drop index 'b': needed in a foreign key constraint
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alter table t3 drop index c;
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ERROR HY000: Cannot drop index 'c': needed in a foreign key constraint
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alter table t4 drop index d;
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ERROR HY000: Cannot drop index 'd': needed in a foreign key constraint
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alter table t2 drop index b;
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ERROR HY000: Cannot drop index 'b': needed in a foreign key constraint
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alter table t2 drop index b, drop index c, drop index d;
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ERROR HY000: Cannot drop index 'b': needed in a foreign key constraint
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create unique index dc on t2 (d,c);
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create index dc on t1 (b,c);
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alter table t2 add primary key (a);
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insert into t1 values (1,1,1);
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insert into t3 values (1,1,1);
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insert into t4 values (1,1,1);
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insert into t2 values (1,1,1,1,1);
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commit;
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alter table t4 add constraint dc foreign key (a) references t1(a);
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show create table t4;
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Table Create Table
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t4 CREATE TABLE `t4` (
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`a` int(11) NOT NULL,
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`d` int(11) NOT NULL,
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`e` int(11) DEFAULT NULL,
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PRIMARY KEY (`a`),
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KEY `d` (`d`),
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CONSTRAINT `dc` FOREIGN KEY (`a`) REFERENCES `t1` (`a`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t3 add constraint dc foreign key (a) references t1(a);
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ERROR HY000: Can't create table '#sql-temporary' (errno: 121)
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show create table t3;
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Table Create Table
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t3 CREATE TABLE `t3` (
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`a` int(11) NOT NULL,
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`c` int(11) NOT NULL,
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`d` int(11) DEFAULT NULL,
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PRIMARY KEY (`a`),
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KEY `c` (`c`)
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) ENGINE=InnoDB DEFAULT CHARSET=latin1
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alter table t2 drop index b, add index (b);
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show create table t2;
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Table Create Table
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t2 CREATE TABLE `t2` (
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`a` int(11) NOT NULL,
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`b` int(11) NOT NULL,
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`c` int(11) NOT NULL,
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`d` int(11) NOT NULL,
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`e` int(11) DEFAULT NULL,
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PRIMARY KEY (`a`),
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UNIQUE KEY `dc` (`d`,`c`),
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KEY `c` (`c`),
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KEY `b` (`b`),
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CONSTRAINT `t2_ibfk_1` FOREIGN KEY (`b`) REFERENCES `t1` (`b`) ON DELETE CASCADE,
|
|
CONSTRAINT `t2_ibfk_2` FOREIGN KEY (`c`) REFERENCES `t3` (`c`),
|
|
CONSTRAINT `t2_ibfk_3` FOREIGN KEY (`d`) REFERENCES `t4` (`d`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
delete from t1;
|
|
ERROR 23000: Cannot delete or update a parent row: a foreign key constraint fails (`test`.`t4`, CONSTRAINT `dc` FOREIGN KEY (`a`) REFERENCES `t1` (`a`))
|
|
drop index dc on t4;
|
|
ERROR 42000: Can't DROP 'dc'; check that column/key exists
|
|
alter table t3 drop foreign key dc;
|
|
ERROR HY000: Error on rename of './test/t3' to '#sql2-temporary' (errno: 152)
|
|
alter table t4 drop foreign key dc;
|
|
select * from t2;
|
|
a b c d e
|
|
1 1 1 1 1
|
|
delete from t1;
|
|
select * from t2;
|
|
a b c d e
|
|
drop table t2,t4,t3,t1;
|
|
create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a))
|
|
engine = innodb default charset=utf8;
|
|
insert into t1 values (1,1,'ab','ab'),(2,2,'ac','ac'),(3,2,'ad','ad'),(4,4,'afe','afe');
|
|
commit;
|
|
alter table t1 add unique index (b);
|
|
ERROR 23000: Duplicate entry '2' for key 'b'
|
|
insert into t1 values(8,9,'fff','fff');
|
|
select * from t1;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=utf8
|
|
alter table t1 add index (b);
|
|
insert into t1 values(10,10,'kkk','iii');
|
|
select * from t1;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
select * from t1 force index(b) order by b;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
explain select * from t1 force index(b) order by b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL b 5 NULL 6
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`),
|
|
KEY `b` (`b`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=utf8
|
|
alter table t1 add unique index (c), add index (d);
|
|
insert into t1 values(11,11,'aaa','mmm');
|
|
select * from t1;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
11 11 aaa mmm
|
|
select * from t1 force index(b) order by b;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
11 11 aaa mmm
|
|
select * from t1 force index(c) order by c;
|
|
a b c d
|
|
11 11 aaa mmm
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
select * from t1 force index(d) order by d;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
11 11 aaa mmm
|
|
explain select * from t1 force index(b) order by b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL b 5 NULL 7
|
|
explain select * from t1 force index(c) order by c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c 31 NULL 7
|
|
explain select * from t1 force index(d) order by d;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL d 63 NULL 7
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`),
|
|
UNIQUE KEY `c` (`c`),
|
|
KEY `b` (`b`),
|
|
KEY `d` (`d`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=utf8
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
drop table t1;
|
|
create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a))
|
|
engine = innodb default charset=ucs2;
|
|
insert into t1 values (1,1,'ab','ab'),(2,2,'ac','ac'),(3,2,'ad','ad'),(4,4,'afe','afe');
|
|
commit;
|
|
alter table t1 add unique index (b);
|
|
ERROR 23000: Duplicate entry '2' for key 'b'
|
|
insert into t1 values(8,9,'fff','fff');
|
|
select * from t1;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=ucs2
|
|
alter table t1 add index (b);
|
|
insert into t1 values(10,10,'kkk','iii');
|
|
select * from t1;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
select * from t1 force index(b) order by b;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
explain select * from t1 force index(b) order by b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL b 5 NULL 6
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`),
|
|
KEY `b` (`b`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=ucs2
|
|
alter table t1 add unique index (c), add index (d);
|
|
insert into t1 values(11,11,'aaa','mmm');
|
|
select * from t1;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
11 11 aaa mmm
|
|
select * from t1 force index(b) order by b;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
11 11 aaa mmm
|
|
select * from t1 force index(c) order by c;
|
|
a b c d
|
|
11 11 aaa mmm
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
select * from t1 force index(d) order by d;
|
|
a b c d
|
|
1 1 ab ab
|
|
2 2 ac ac
|
|
3 2 ad ad
|
|
4 4 afe afe
|
|
8 9 fff fff
|
|
10 10 kkk iii
|
|
11 11 aaa mmm
|
|
explain select * from t1 force index(b) order by b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL b 5 NULL 7
|
|
explain select * from t1 force index(c) order by c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c 21 NULL 7
|
|
explain select * from t1 force index(d) order by d;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL d 43 NULL 7
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`),
|
|
UNIQUE KEY `c` (`c`),
|
|
KEY `b` (`b`),
|
|
KEY `d` (`d`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=ucs2
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
drop table t1;
|
|
create table t1(a int not null, b int) engine = innodb;
|
|
insert into t1 values (1,1),(1,1),(1,1),(1,1);
|
|
alter table t1 add unique index (a);
|
|
ERROR 23000: Duplicate entry '1' for key 'a'
|
|
alter table t1 add unique index (b);
|
|
ERROR 23000: Duplicate entry '1' for key 'b'
|
|
alter table t1 add unique index (a), add unique index(b);
|
|
ERROR 23000: Duplicate entry '1' for key 'a'
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
drop table t1;
|
|
create table t1(a int not null, c int not null,b int, primary key(a), unique key(c), key(b)) engine = innodb;
|
|
alter table t1 drop index c, drop index b;
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`c` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
PRIMARY KEY (`a`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
drop table t1;
|
|
create table t1(a int not null, b int, primary key(a)) engine = innodb;
|
|
alter table t1 add index (b);
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
PRIMARY KEY (`a`),
|
|
KEY `b` (`b`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
drop table t1;
|
|
create table t1(a int not null, b int, c char(10), d varchar(20), primary key (a)) engine = innodb;
|
|
insert into t1 values (1,1,'ab','ab'),(2,2,'ac','ac'),(3,3,'ac','ac'),(4,4,'afe','afe');
|
|
alter table t1 add unique index (b), add unique index (c), add unique index (d);
|
|
ERROR 23000: Duplicate entry 'ac' for key 'c'
|
|
alter table t1 add unique index (b), add index (d), add unique index (c);
|
|
ERROR 23000: Duplicate entry 'ac' for key 'c'
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) DEFAULT NULL,
|
|
`c` char(10) DEFAULT NULL,
|
|
`d` varchar(20) DEFAULT NULL,
|
|
PRIMARY KEY (`a`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
drop table t1;
|
|
create table t1(a int not null, b int not null, c int, primary key (a), key(c)) engine=innodb;
|
|
insert into t1 values (5,1,5),(4,2,4),(3,3,3),(2,4,2),(1,5,1);
|
|
alter table t1 add unique index (b);
|
|
insert into t1 values (10,20,20),(11,19,19),(12,18,18),(13,17,17);
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) NOT NULL,
|
|
`c` int(11) DEFAULT NULL,
|
|
PRIMARY KEY (`a`),
|
|
UNIQUE KEY `b` (`b`),
|
|
KEY `c` (`c`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
explain select * from t1 force index(c) order by c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL c 5 NULL 9
|
|
explain select * from t1 order by a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL PRIMARY 4 NULL 9
|
|
explain select * from t1 force index(b) order by b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL b 4 NULL 9
|
|
select * from t1 order by a;
|
|
a b c
|
|
1 5 1
|
|
2 4 2
|
|
3 3 3
|
|
4 2 4
|
|
5 1 5
|
|
10 20 20
|
|
11 19 19
|
|
12 18 18
|
|
13 17 17
|
|
select * from t1 force index(b) order by b;
|
|
a b c
|
|
5 1 5
|
|
4 2 4
|
|
3 3 3
|
|
2 4 2
|
|
1 5 1
|
|
13 17 17
|
|
12 18 18
|
|
11 19 19
|
|
10 20 20
|
|
select * from t1 force index(c) order by c;
|
|
a b c
|
|
1 5 1
|
|
2 4 2
|
|
3 3 3
|
|
4 2 4
|
|
5 1 5
|
|
13 17 17
|
|
12 18 18
|
|
11 19 19
|
|
10 20 20
|
|
drop table t1;
|
|
create table t1(a int not null, b int not null) engine=innodb;
|
|
insert into t1 values (1,1);
|
|
alter table t1 add primary key(b);
|
|
insert into t1 values (2,2);
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
`b` int(11) NOT NULL,
|
|
PRIMARY KEY (`b`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
select * from t1;
|
|
a b
|
|
1 1
|
|
2 2
|
|
explain select * from t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
|
|
explain select * from t1 order by a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 Using filesort
|
|
explain select * from t1 order by b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL PRIMARY 4 NULL 2
|
|
checksum table t1;
|
|
Table Checksum
|
|
test.t1 582702641
|
|
drop table t1;
|
|
create table t1(a int not null) engine=innodb;
|
|
insert into t1 values (1);
|
|
alter table t1 add primary key(a);
|
|
insert into t1 values (2);
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL,
|
|
PRIMARY KEY (`a`)
|
|
) ENGINE=InnoDB DEFAULT CHARSET=latin1
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
commit;
|
|
select * from t1;
|
|
a
|
|
1
|
|
2
|
|
explain select * from t1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL PRIMARY 4 NULL 2 Using index
|
|
explain select * from t1 order by a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL PRIMARY 4 NULL 2 Using index
|
|
drop table t1;
|
|
create table t2(d varchar(17) primary key) engine=innodb default charset=utf8;
|
|
create table t3(a int primary key) engine=innodb;
|
|
insert into t3 values(22),(44),(33),(55),(66);
|
|
insert into t2 values ('jejdkrun87'),('adfd72nh9k'),
|
|
('adfdpplkeock'),('adfdijnmnb78k'),('adfdijn0loKNHJik');
|
|
create table t1(a int, b blob, c text, d text not null)
|
|
engine=innodb default charset = utf8;
|
|
insert into t1 values (null,null,null,'null');
|
|
insert into t1
|
|
select a,left(repeat(d,100*a),65535),repeat(d,20*a),d from t2,t3;
|
|
drop table t2, t3;
|
|
select count(*) from t1 where a=44;
|
|
count(*)
|
|
5
|
|
select a,
|
|
length(b),b=left(repeat(d,100*a),65535),length(c),c=repeat(d,20*a),d from t1;
|
|
a length(b) b=left(repeat(d,100*a),65535) length(c) c=repeat(d,20*a) d
|
|
NULL NULL NULL NULL NULL null
|
|
22 22000 1 4400 1 adfd72nh9k
|
|
22 35200 1 7040 1 adfdijn0loKNHJik
|
|
22 28600 1 5720 1 adfdijnmnb78k
|
|
22 26400 1 5280 1 adfdpplkeock
|
|
22 22000 1 4400 1 jejdkrun87
|
|
33 33000 1 6600 1 adfd72nh9k
|
|
33 52800 1 10560 1 adfdijn0loKNHJik
|
|
33 42900 1 8580 1 adfdijnmnb78k
|
|
33 39600 1 7920 1 adfdpplkeock
|
|
33 33000 1 6600 1 jejdkrun87
|
|
44 44000 1 8800 1 adfd72nh9k
|
|
44 65535 1 14080 1 adfdijn0loKNHJik
|
|
44 57200 1 11440 1 adfdijnmnb78k
|
|
44 52800 1 10560 1 adfdpplkeock
|
|
44 44000 1 8800 1 jejdkrun87
|
|
55 55000 1 11000 1 adfd72nh9k
|
|
55 65535 1 17600 1 adfdijn0loKNHJik
|
|
55 65535 1 14300 1 adfdijnmnb78k
|
|
55 65535 1 13200 1 adfdpplkeock
|
|
55 55000 1 11000 1 jejdkrun87
|
|
66 65535 1 13200 1 adfd72nh9k
|
|
66 65535 1 21120 1 adfdijn0loKNHJik
|
|
66 65535 1 17160 1 adfdijnmnb78k
|
|
66 65535 1 15840 1 adfdpplkeock
|
|
66 65535 1 13200 1 jejdkrun87
|
|
alter table t1 add primary key (a), add key (b(20));
|
|
ERROR 42000: All parts of a PRIMARY KEY must be NOT NULL; if you need NULL in a key, use UNIQUE instead
|
|
delete from t1 where d='null';
|
|
alter table t1 add primary key (a), add key (b(20));
|
|
ERROR 23000: Duplicate entry '22' for key 'PRIMARY'
|
|
delete from t1 where a%2;
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
alter table t1 add primary key (a,b(255),c(255)), add key (b(767));
|
|
select count(*) from t1 where a=44;
|
|
count(*)
|
|
5
|
|
select a,
|
|
length(b),b=left(repeat(d,100*a),65535),length(c),c=repeat(d,20*a),d from t1;
|
|
a length(b) b=left(repeat(d,100*a),65535) length(c) c=repeat(d,20*a) d
|
|
22 22000 1 4400 1 adfd72nh9k
|
|
22 35200 1 7040 1 adfdijn0loKNHJik
|
|
22 28600 1 5720 1 adfdijnmnb78k
|
|
22 26400 1 5280 1 adfdpplkeock
|
|
22 22000 1 4400 1 jejdkrun87
|
|
44 44000 1 8800 1 adfd72nh9k
|
|
44 65535 1 14080 1 adfdijn0loKNHJik
|
|
44 57200 1 11440 1 adfdijnmnb78k
|
|
44 52800 1 10560 1 adfdpplkeock
|
|
44 44000 1 8800 1 jejdkrun87
|
|
66 65535 1 13200 1 adfd72nh9k
|
|
66 65535 1 21120 1 adfdijn0loKNHJik
|
|
66 65535 1 17160 1 adfdijnmnb78k
|
|
66 65535 1 15840 1 adfdpplkeock
|
|
66 65535 1 13200 1 jejdkrun87
|
|
show create table t1;
|
|
Table Create Table
|
|
t1 CREATE TABLE `t1` (
|
|
`a` int(11) NOT NULL DEFAULT '0',
|
|
`b` blob NOT NULL,
|
|
`c` text NOT NULL,
|
|
`d` text NOT NULL,
|
|
PRIMARY KEY (`a`,`b`(255),`c`(255)),
|
|
KEY `b` (`b`(767))
|
|
) ENGINE=InnoDB DEFAULT CHARSET=utf8
|
|
check table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 check status OK
|
|
explain select * from t1 where b like 'adfd%';
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range b b 769 NULL 11 Using where
|
|
drop table t1;
|