Description:
MySQL returns wrong user variable value(see 'SELECT @bar;' result),
found during bug#47371 fixing.
How to repeat:
create table t1 (libname varchar(21) not null, city text, primary key (libname));
create table t2 (isbn varchar(21) not null, author text, title text, primary key (isbn));
create table t3 (isbn varchar(21) not null, libname varchar(21) not null, quantity int ,primary key (isbn,libname));
insert into t2 values ('001','Daffy','A duck''s life');
insert into t2 values ('002','Bugs','A rabbit\'s life');
insert into t2 values ('003','Cowboy','Life on the range');
insert into t2 values ('000','Anonymous','Wanna buy this book?');
insert into t2 values ('004','Best Seller','One Heckuva book');
insert into t2 values ('005','EveryoneBuys','This very book');
insert into t2 values ('006','San Fran','It is a san fran lifestyle');
insert into t2 values ('007','BerkAuthor','Cool.Berkley.the.book');
insert into t3 values('000','New York Public Libra','1');
insert into t3 values('001','New York Public Libra','2');
insert into t3 values('002','New York Public Libra','3');
insert into t3 values('003','New York Public Libra','4');
insert into t3 values('004','New York Public Libra','5');
insert into t3 values('005','New York Public Libra','6');
insert into t3 values('006','San Fransisco Public','5');
insert into t3 values('007','Berkeley Public1','3');
insert into t3 values('007','Berkeley Public2','3');
insert into t3 values('001','NYC Lib','8');
insert into t1 values ('New York Public Libra','New York');
insert into t1 values ('San Fransisco Public','San Fran');
insert into t1 values ('Berkeley Public1','Berkeley');
insert into t1 values ('Berkeley Public2','Berkeley');
insert into t1 values ('NYC Lib','New York');
select t2.isbn,city,@bar:=t1.libname,count(distinct t1.libname) as a
from t3 left join t1 on t3.libname=t1.libname left join t2
on t3.isbn=t2.isbn group by city having count(distinct
t1.libname) > 1;
SELECT @bar;
