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363fd89b92
BitKeeper/etc/ignore: auto-union BitKeeper/deleted/.del-configure.in~ac795a92c8fe049c: Auto merged include/my_sys.h: Auto merged mysql-test/mysql-test-run.sh: Auto merged mysql-test/t/count_distinct.test: Auto merged sql/ha_innodb.cc: Auto merged sql/item_sum.cc: Auto merged sql/sql_acl.cc: Auto merged
57 lines
2.6 KiB
Text
57 lines
2.6 KiB
Text
#
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# Problem with count(distinct)
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#
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--disable_warnings
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drop table if exists t1,t2,t3;
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--enable_warnings
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create table t1 (libname varchar(21) not null, city text, primary key (libname));
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create table t2 (isbn varchar(21) not null, author text, title text, primary key (isbn));
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create table t3 (isbn varchar(21) not null, libname varchar(21) not null, quantity int ,primary key (isbn,libname));
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insert into t2 values ('001','Daffy','A duck''s life');
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insert into t2 values ('002','Bugs','A rabbit\'s life');
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insert into t2 values ('003','Cowboy','Life on the range');
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insert into t2 values ('000','Anonymous','Wanna buy this book?');
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insert into t2 values ('004','Best Seller','One Heckuva book');
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insert into t2 values ('005','EveryoneBuys','This very book');
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insert into t2 values ('006','San Fran','It is a san fran lifestyle');
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insert into t2 values ('007','BerkAuthor','Cool.Berkley.the.book');
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insert into t3 values('000','New York Public Libra','1');
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insert into t3 values('001','New York Public Libra','2');
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insert into t3 values('002','New York Public Libra','3');
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insert into t3 values('003','New York Public Libra','4');
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insert into t3 values('004','New York Public Libra','5');
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insert into t3 values('005','New York Public Libra','6');
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insert into t3 values('006','San Fransisco Public','5');
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insert into t3 values('007','Berkeley Public1','3');
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insert into t3 values('007','Berkeley Public2','3');
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insert into t3 values('001','NYC Lib','8');
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insert into t1 values ('New York Public Libra','New York');
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insert into t1 values ('San Fransisco Public','San Fran');
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insert into t1 values ('Berkeley Public1','Berkeley');
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insert into t1 values ('Berkeley Public2','Berkeley');
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insert into t1 values ('NYC Lib','New York');
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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;
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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;
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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;
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drop table t1, t2, t3;
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#
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# Problem with LEFT JOIN
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#
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create table t1 (f1 int);
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insert into t1 values (1);
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create table t2 (f1 int,f2 int);
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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;
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drop table t1,t2;
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#
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# Empty tables
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#
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create table t1 (f int);
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select count(distinct f) from t1;
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drop table t1;
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