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drop table if exists t1,t2;
create table t1 (name char(20) not null, primary key (name));
create table t2 (name char(20) binary not null, primary key (name));
insert into t1 values ("");
insert into t1 values ("");
insert into t1 values ("");
insert into t2 select * from t1;
select * from t1 order by name;
name
select concat("*",name,"*") from t1 order by 1;
concat("*",name,"*")
**
**
**
select min(name),min(concat("*",name,"*")),max(name),max(concat("*",name,"*")) from t1;
min(name) min(concat("*",name,"*")) max(name) max(concat("*",name,"*"))
** **
select * from t2 order by name;
name
select concat("*",name,"*") from t2 order by 1;
concat("*",name,"*")
**
**
**
select min(name),min(concat("*",name,"*")),max(name),max(concat("*",name,"*")) from t2;
min(name) min(concat("*",name,"*")) max(name) max(concat("*",name,"*"))
** **
select name from t1 where name between '' and '';
name
select name from t2 where name between '' and '';
name
select name from t2 where name between '' and '';
name
drop table t1,t2;
create table t1 (a char(10) not null, b char(10) binary not null,key (a), key(b));
insert into t1 values ("hello ","hello "),("hello2 ","hello2 ");
select * from t1 where a="hello";
a b
hello hello
select * from t1 where a="hello ";
a b
hello hello
select * from t1 ignore index (a) where a="hello ";
a b
hello hello
select * from t1 where b="hello";
a b
hello hello
select * from t1 where b="hello ";
a b
hello hello
select * from t1 ignore index (b) where b="hello ";
a b
alter table t1 modify b tinytext not null, drop key b, add key (b(100));
select * from t1 where b="hello ";
a b
hello hello
select * from t1 ignore index (b) where b="hello ";
a b
hello hello
drop table t1;
create table t1 (b char(8));
insert into t1 values(NULL);
select b from t1 where binary b like '';
b
select b from t1 group by binary b like '';
b
NULL
select b from t1 having binary b like '';
b
drop table t1;
create table t1( firstname char(20), lastname char(20));
insert into t1 values ("john","doe"),("John","Doe");
select * from t1 where firstname='john' and firstname like binary 'john';
firstname lastname
john doe
select * from t1 where firstname='john' and binary 'john' = firstname;
firstname lastname
john doe
select * from t1 where firstname='john' and firstname = binary 'john';
firstname lastname
john doe
select * from t1 where firstname='John' and firstname like binary 'john';
firstname lastname
john doe
select * from t1 where firstname='john' and firstname like binary 'John';
firstname lastname
John Doe
drop table t1;
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