# # Bug with distinct and INSERT INTO # Bug with group by and not used fields # drop table if exists t1,t2,t3; CREATE TABLE t1 (id int,facility char(20)); CREATE TABLE t2 (facility char(20)); INSERT INTO t1 VALUES (NULL,NULL); INSERT INTO t1 VALUES (-1,''); INSERT INTO t1 VALUES (0,''); INSERT INTO t1 VALUES (1,'/L'); INSERT INTO t1 VALUES (2,'A01'); INSERT INTO t1 VALUES (3,'ANC'); INSERT INTO t1 VALUES (4,'F01'); INSERT INTO t1 VALUES (5,'FBX'); INSERT INTO t1 VALUES (6,'MT'); INSERT INTO t1 VALUES (7,'P'); INSERT INTO t1 VALUES (8,'RV'); INSERT INTO t1 VALUES (9,'SRV'); INSERT INTO t1 VALUES (10,'VMT'); INSERT INTO t2 SELECT DISTINCT FACILITY FROM t1; select id from t1 group by id; select * from t1 order by id; select id-5,facility from t1 order by "id-5"; select id,concat(facility) from t1 group by id ; select id+0 as a,max(id),concat(facility) as b from t1 group by a order by b desc,a; select id >= 0 and id <= 5 as grp,count(*) from t1 group by grp; SELECT DISTINCT FACILITY FROM t1; SELECT FACILITY FROM t2; SELECT count(*) from t1,t2 where t1.facility=t2.facility; select count(facility) from t1; select count(*) from t1; select count(*) from t1 where facility IS NULL; select count(*) from t1 where facility = NULL; select count(*) from t1 where facility IS NOT NULL; select count(*) from t1 where id IS NULL; select count(*) from t1 where id IS NOT NULL; drop table t1,t2; # # Problem with distinct without results # CREATE TABLE t1 (UserId int(11) DEFAULT '0' NOT NULL); INSERT INTO t1 VALUES (20); INSERT INTO t1 VALUES (27); SELECT UserId FROM t1 WHERE Userid=22; SELECT UserId FROM t1 WHERE UserId=22 group by Userid; SELECT DISTINCT UserId FROM t1 WHERE UserId=22 group by Userid; SELECT DISTINCT UserId FROM t1 WHERE UserId=22; drop table t1; # # Test of distinct # CREATE TABLE t1 (a int(10) unsigned not null primary key,b int(10) unsigned); INSERT INTO t1 VALUES (1,1),(2,1); CREATE TABLE t2 (a int(10) unsigned not null, key (A)); INSERT INTO t2 VALUES (1),(2); CREATE TABLE t3 (a int(10) unsigned, key(A), b text); INSERT INTO t3 VALUES (1,'1'),(2,'2'); SELECT DISTINCT t3.b FROM t3,t2,t1 WHERE t3.a=t1.b AND t1.a=t2.a; INSERT INTO t2 values (1),(2),(3); INSERT INTO t3 VALUES (1,'1'),(2,'2'),(1,'1'),(2,'2'); explain SELECT distinct t3.a FROM t3,t2,t1 WHERE t3.a=t1.b AND t1.a=t2.a; SELECT distinct t3.a FROM t3,t2,t1 WHERE t3.a=t1.b AND t1.a=t2.a; # Create a lot of data into t3; create temporary table t4 select * from t3; insert into t3 select * from t4; insert into t4 select * from t3; insert into t3 select * from t4; insert into t4 select * from t3; insert into t3 select * from t4; insert into t4 select * from t3; insert into t3 select * from t4; explain select distinct t1.a from t1,t3 where t1.a=t3.a; #flush status; select distinct t1.a from t1,t3 where t1.a=t3.a; #show status like 'Handler%'; #flush status; select distinct 1 from t1,t3 where t1.a=t3.a; #show status like 'Handler%'; drop table t1,t2,t3,t4; CREATE TABLE t1 (name varchar(255)); INSERT INTO t1 VALUES ('aa'),('ab'),('ac'),('ad'),('ae'); SELECT DISTINCT * FROM t1 LIMIT 2; SELECT DISTINCT name FROM t1 LIMIT 2; SELECT DISTINCT 1 FROM t1 LIMIT 2; drop table t1; CREATE TABLE t1 ( ID int(11) NOT NULL auto_increment, NAME varchar(75) DEFAULT '' NOT NULL, LINK_ID int(11) DEFAULT '0' NOT NULL, PRIMARY KEY (ID), KEY NAME (NAME), KEY LINK_ID (LINK_ID) ); INSERT INTO t1 (ID, NAME, LINK_ID) VALUES (1,'Mike',0),(2,'Jack',0),(3,'Bill',0); CREATE TABLE t2 ( ID int(11) NOT NULL auto_increment, NAME varchar(150) DEFAULT '' NOT NULL, PRIMARY KEY (ID), KEY NAME (NAME) ); SELECT DISTINCT t2.id AS key_link_id, t2.name AS link FROM t1 LEFT JOIN t2 ON t1.link_id=t2.id GROUP BY t1.id ORDER BY link; drop table t1,t2; # # Problem with table dependencies # create table t1 ( id int not null, name tinytext not null, unique (id) ); create table t2 ( id int not null, idx int not null, unique (id, idx) ); create table t3 ( id int not null, idx int not null, unique (id, idx) ); insert into t1 values (1,'yes'), (2,'no'); insert into t2 values (1,1); insert into t3 values (1,1); EXPLAIN SELECT DISTINCT t1.id from t1 straight_join t2 straight_join t3 straight_join t1 as j_lj_t2 left join t2 as t2_lj on j_lj_t2.id=t2_lj.id straight_join t1 as j_lj_t3 left join t3 as t3_lj on j_lj_t3.id=t3_lj.id WHERE ((t1.id=j_lj_t2.id AND t2_lj.id IS NULL) OR (t1.id=t2.id AND t2.idx=2)) AND ((t1.id=j_lj_t3.id AND t3_lj.id IS NULL) OR (t1.id=t3.id AND t3.idx=2)); SELECT DISTINCT t1.id from t1 straight_join t2 straight_join t3 straight_join t1 as j_lj_t2 left join t2 as t2_lj on j_lj_t2.id=t2_lj.id straight_join t1 as j_lj_t3 left join t3 as t3_lj on j_lj_t3.id=t3_lj.id WHERE ((t1.id=j_lj_t2.id AND t2_lj.id IS NULL) OR (t1.id=t2.id AND t2.idx=2)) AND ((t1.id=j_lj_t3.id AND t3_lj.id IS NULL) OR (t1.id=t3.id AND t3.idx=2)); drop table t1,t2,t3; # # Test using DISTINCT on a function that contains a group function # This also test the case when one doesn't use all fields in GROUP BY. # drop table if exists t1; create table t1 (a int not null, b int not null, t time); insert into t1 values (1,1,"00:06:15"),(1,2,"00:06:15"),(1,2,"00:30:15"),(1,3,"00:06:15"),(1,3,"00:30:15"); select a,sec_to_time(sum(time_to_sec(t))) from t1 group by a,b; select distinct a,sec_to_time(sum(time_to_sec(t))) from t1 group by a,b; create table t2 (a int not null primary key, b int); insert into t2 values (1,1),(2,2),(3,3); select t1.a,sec_to_time(sum(time_to_sec(t))) from t1 left join t2 on (t1.b=t2.a) group by t1.a,t2.b; select distinct t1.a,sec_to_time(sum(time_to_sec(t))) from t1 left join t2 on (t1.b=t2.a) group by t1.a,t2.b; drop table t1,t2; # # Test problem with DISTINCT and HAVING # create table t1 (a int not null,b char(5), c text); insert into t1 (a) values (1),(2),(3),(4),(1),(2),(3),(4); select distinct a from t1 group by b,a having a > 2 order by a desc; select distinct a,c from t1 group by b,c,a having a > 2 order by a desc; drop table t1; # # Test problem with DISTINCT and ORDER BY DESC # create table t1 (a char(1), key(a)) type=myisam; insert into t1 values('1'),('1'); select * from t1 where a >= '1'; select distinct a from t1 order by a desc; select distinct a from t1 where a >= '1' order by a desc; drop table t1; # # Test when using a not previously used column in ORDER BY # CREATE TABLE t1 (email varchar(50), infoID BIGINT, dateentered DATETIME); CREATE TABLE t2 (infoID BIGINT, shipcode varchar(10)); INSERT INTO t1 (email, infoID, dateentered) VALUES ('test1@testdomain.com', 1, '2002-07-30 22:56:38'), ('test1@testdomain.com', 1, '2002-07-27 22:58:16'), ('test2@testdomain.com', 1, '2002-06-19 15:22:19'), ('test2@testdomain.com', 2, '2002-06-18 14:23:47'), ('test3@testdomain.com', 1, '2002-05-19 22:17:32'); INSERT INTO t2(infoID, shipcode) VALUES (1, 'Z001'), (2, 'R002'); SELECT DISTINCTROW email, shipcode FROM t1, t2 WHERE t1.infoID=t2.infoID; SELECT DISTINCTROW email FROM t1 ORDER BY dateentered DESC; SELECT DISTINCTROW email, shipcode FROM t1, t2 WHERE t1.infoID=t2.infoID ORDER BY dateentered DESC; drop table t1,t2;