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📄 count_distinct.test

📁 这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置
💻 TEST
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## Problem with count(distinct)#--disable_warningsdrop table if exists t1,t2,t3;--enable_warningscreate 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,t1.libname,count(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,t1.libname;select t2.isbn,city,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 t2.isbn,city,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 concat(t1.libname,'a')) > 1;drop table t1, t2, t3;## Problem with LEFT JOIN#create table t1 (f1 int);insert into t1 values (1);create table t2 (f1 int,f2 int);select t1.f1,count(distinct t2.f2),count(distinct 1,NULL) from t1 left join t2 on t1.f1=t2.f1 group by t1.f1;drop table t1,t2;## Empty tables#create table t1 (f int);select count(distinct f) from t1;drop table t1;# End of 4.1 tests## Bug #6515#create table t1 (a char(3), b char(20), primary key (a, b));insert into t1 values ('ABW', 'Dutch'), ('ABW', 'English');select count(distinct a) from t1 group by b;drop table t1;## Bug #9593 "The combination of COUNT, DISTINCT and CONCAT #            seems to lock the server"# Bug appears only on Windows system#create table t1 (f1 int, f2 int);insert into t1 values (0,1),(1,2);select count(distinct if(f1,3,f2)) from t1;drop table t1;

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