# Initialise
--disable_warnings
drop table if exists t1,t2,t3;
--enable_warnings

#
# Simple test without tables

-- error 1111
SELECT 1 FROM (SELECT 1) as a  GROUP BY SUM(1);

#
# Test of group (Failed for Lars Hoss <lh@pbm.de>)
#

CREATE TABLE t1 (
  spID int(10) unsigned,
  userID int(10) unsigned,
  score smallint(5) unsigned,
  lsg char(40),
  date date
);

INSERT INTO t1 VALUES (1,1,1,'','0000-00-00');
INSERT INTO t1 VALUES (2,2,2,'','0000-00-00');
INSERT INTO t1 VALUES (2,1,1,'','0000-00-00');
INSERT INTO t1 VALUES (3,3,3,'','0000-00-00');

CREATE TABLE t2 (
  userID int(10) unsigned NOT NULL auto_increment,
  niName char(15),
  passwd char(8),
  mail char(50),
  isAukt enum('N','Y') DEFAULT 'N',
  vName char(30),
  nName char(40),
  adr char(60),
  plz char(5),
  ort char(35),
  land char(20),
  PRIMARY KEY (userID)
);

INSERT INTO t2 VALUES (1,'name','pass','mail','Y','v','n','adr','1','1','1');
INSERT INTO t2 VALUES (2,'name','pass','mail','Y','v','n','adr','1','1','1');
INSERT INTO t2 VALUES (3,'name','pass','mail','Y','v','n','adr','1','1','1');
INSERT INTO t2 VALUES (4,'name','pass','mail','Y','v','n','adr','1','1','1');
INSERT INTO t2 VALUES (5,'name','pass','mail','Y','v','n','adr','1','1','1');

SELECT t2.userid, MIN(t1.score) FROM t1, t2 WHERE t1.userID=t2.userID GROUP BY t2.userid;
SELECT t2.userid, MIN(t1.score) FROM t1, t2 WHERE t1.userID=t2.userID GROUP BY t2.userid ORDER BY NULL;
SELECT t2.userid, MIN(t1.score) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2  GROUP BY t2.userid;
SELECT t2.userid, MIN(t1.score+0.0) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2  GROUP BY t2.userid;
SELECT t2.userid, MIN(t1.score+0.0) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2  GROUP BY t2.userid ORDER BY NULL;
EXPLAIN SELECT t2.userid, MIN(t1.score+0.0) FROM t1, t2 WHERE t1.userID=t2.userID AND t1.spID=2  GROUP BY t2.userid ORDER BY NULL;
drop table t1,t2;

#
# Bug in GROUP BY, by Nikki Chumakov <nikki@saddam.cityline.ru>
#

CREATE TABLE t1 (
  PID int(10) unsigned NOT NULL auto_increment,
  payDate date DEFAULT '0000-00-00' NOT NULL,
  recDate datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
  URID int(10) unsigned DEFAULT '0' NOT NULL,
  CRID int(10) unsigned DEFAULT '0' NOT NULL,
  amount int(10) unsigned DEFAULT '0' NOT NULL,
  operator int(10) unsigned,
  method enum('unknown','cash','dealer','check','card','lazy','delayed','test') DEFAULT 'unknown' NOT NULL,
  DIID int(10) unsigned,
  reason char(1) binary DEFAULT '' NOT NULL,
  code_id int(10) unsigned,
  qty mediumint(8) unsigned DEFAULT '0' NOT NULL,
  PRIMARY KEY (PID),
  KEY URID (URID),
  KEY reason (reason),
  KEY method (method),
  KEY payDate (payDate)
);

INSERT INTO t1 VALUES (1,'1970-01-01','1997-10-17 00:00:00',2529,1,21000,11886,'check',0,'F',16200,6);

--error 1056
SELECT COUNT(P.URID),SUM(P.amount),P.method, MIN(PP.recdate+0) > 19980501000000   AS IsNew FROM t1 AS P JOIN t1 as PP WHERE P.URID = PP.URID GROUP BY method,IsNew;

drop table t1;

#
# Problem with GROUP BY + ORDER BY when no match
# Tested with locking
#

CREATE TABLE t1 (
  cid mediumint(9) NOT NULL auto_increment,
  firstname varchar(32) DEFAULT '' NOT NULL,
  surname varchar(32) DEFAULT '' NOT NULL,
  PRIMARY KEY (cid)
);
INSERT INTO t1 VALUES (1,'That','Guy');
INSERT INTO t1 VALUES (2,'Another','Gent');

CREATE TABLE t2 (
  call_id mediumint(8) NOT NULL auto_increment,
  contact_id mediumint(8) DEFAULT '0' NOT NULL,
  PRIMARY KEY (call_id),
  KEY contact_id (contact_id)
);

lock tables t1 read,t2 write;

INSERT INTO t2 VALUES (10,2);
INSERT INTO t2 VALUES (18,2);
INSERT INTO t2 VALUES (62,2);
INSERT INTO t2 VALUES (91,2);
INSERT INTO t2 VALUES (92,2);

SELECT cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid;
SELECT cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY NULL;
SELECT HIGH_PRIORITY cid, CONCAT(firstname, ' ', surname), COUNT(call_id) FROM t1 LEFT JOIN t2 ON cid=contact_id WHERE firstname like '%foo%' GROUP BY cid ORDER BY surname, firstname;

drop table t1,t2;
unlock tables;

#
# Test of group by bug in bugzilla
#

CREATE TABLE t1 (
  bug_id mediumint(9) NOT NULL auto_increment,
  groupset bigint(20) DEFAULT '0' NOT NULL,
  assigned_to mediumint(9) DEFAULT '0' NOT NULL,
  bug_file_loc text,
  bug_severity enum('blocker','critical','major','normal','minor','trivial','enhancement') DEFAULT 'blocker' NOT NULL,
  bug_status enum('','NEW','ASSIGNED','REOPENED','RESOLVED','VERIFIED','CLOSED') DEFAULT 'NEW' NOT NULL,
  creation_ts datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
  delta_ts timestamp,
  short_desc mediumtext,
  long_desc mediumtext,
  op_sys enum('All','Windows 3.1','Windows 95','Windows 98','Windows NT','Windows 2000','Linux','other') DEFAULT 'All' NOT NULL,
  priority enum('P1','P2','P3','P4','P5') DEFAULT 'P1' NOT NULL,
  product varchar(64) DEFAULT '' NOT NULL,
  rep_platform enum('All','PC','VTD-8','Other'),
  reporter mediumint(9) DEFAULT '0' NOT NULL,
  version varchar(16) DEFAULT '' NOT NULL,
  component varchar(50) DEFAULT '' NOT NULL,
  resolution enum('','FIXED','INVALID','WONTFIX','LATER','REMIND','DUPLICATE','WORKSFORME') DEFAULT '' NOT NULL,
  target_milestone varchar(20) DEFAULT '' NOT NULL,
  qa_contact mediumint(9) DEFAULT '0' NOT NULL,
  status_whiteboard mediumtext NOT NULL,
  votes mediumint(9) DEFAULT '0' NOT NULL,
  PRIMARY KEY (bug_id),
  KEY assigned_to (assigned_to),
  KEY creation_ts (creation_ts),
  KEY delta_ts (delta_ts),
  KEY bug_severity (bug_severity),
  KEY bug_status (bug_status),
  KEY op_sys (op_sys),
  KEY priority (priority),
  KEY product (product),
  KEY reporter (reporter),
  KEY version (version),
  KEY component (component),
  KEY resolution (resolution),
  KEY target_milestone (target_milestone),
  KEY qa_contact (qa_contact),
  KEY votes (votes)
);

INSERT INTO t1 VALUES (1,0,0,'','normal','','2000-02-10 09:25:12',20000321114747,'','','Linux','P1','TestProduct','PC',3,'other','TestComponent','','M1',0,'',0);
INSERT INTO t1 VALUES (9,0,0,'','enhancement','','2000-03-10 11:49:36',20000321114747,'','','All','P5','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - conversion','','',0,'',0);
INSERT INTO t1 VALUES (10,0,0,'','enhancement','','2000-03-10 18:10:16',20000321114747,'','','All','P4','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - conversion','','',0,'',0);
INSERT INTO t1 VALUES (7,0,0,'','critical','','2000-03-09 10:50:21',20000321114747,'','','All','P1','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - generic','','',0,'',0);
INSERT INTO t1 VALUES (6,0,0,'','normal','','2000-03-09 10:42:44',20000321114747,'','','All','P2','AAAAA','PC',3,'2.00 CD - Pre','kkkkkkkkkkk lllllllllll','','',0,'',0);
INSERT INTO t1 VALUES (8,0,0,'','major','','2000-03-09 11:32:14',20000321114747,'','','All','P3','AAAAA','PC',3,'2.00 CD - Pre','kkkkkkkkkkk lllllllllll','','',0,'',0);
INSERT INTO t1 VALUES (5,0,0,'','enhancement','','2000-03-09 10:38:59',20000321114747,'','','All','P5','CCC/CCCCCC','PC',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (4,0,0,'','normal','','2000-03-08 18:32:14',20000321114747,'','','other','P2','TestProduct','Other',3,'other','TestComponent2','','',0,'',0);
INSERT INTO t1 VALUES (3,0,0,'','normal','','2000-03-08 18:30:52',20000321114747,'','','other','P2','TestProduct','Other',3,'other','TestComponent','','',0,'',0);
INSERT INTO t1 VALUES (2,0,0,'','enhancement','','2000-03-08 18:24:51',20000321114747,'','','All','P2','TestProduct','Other',4,'other','TestComponent2','','',0,'',0);
INSERT INTO t1 VALUES (11,0,0,'','blocker','','2000-03-13 09:43:41',20000321114747,'','','All','P2','CCC/CCCCCC','PC',5,'7.00','DDDDDDDDD','','',0,'',0);
INSERT INTO t1 VALUES (12,0,0,'','normal','','2000-03-13 16:14:31',20000321114747,'','','All','P2','AAAAA','PC',3,'2.00 CD - Pre','kkkkkkkkkkk lllllllllll','','',0,'',0);
INSERT INTO t1 VALUES (13,0,0,'','normal','','2000-03-15 16:20:44',20000321114747,'','','other','P2','TestProduct','Other',3,'other','TestComponent','','',0,'',0);
INSERT INTO t1 VALUES (14,0,0,'','blocker','','2000-03-15 18:13:47',20000321114747,'','','All','P1','AAAAA','PC',3,'2.00 CD - Pre','BBBBBBBBBBBBB - generic','','',0,'',0);
INSERT INTO t1 VALUES (15,0,0,'','minor','','2000-03-16 18:03:28',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','DDDDDDDDD','','',0,'',0);
INSERT INTO t1 VALUES (16,0,0,'','normal','','2000-03-16 18:33:41',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (17,0,0,'','normal','','2000-03-16 18:34:18',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (18,0,0,'','normal','','2000-03-16 18:34:56',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (19,0,0,'','enhancement','','2000-03-16 18:35:34',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (20,0,0,'','enhancement','','2000-03-16 18:36:23',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (21,0,0,'','enhancement','','2000-03-16 18:37:23',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (22,0,0,'','enhancement','','2000-03-16 18:38:16',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','Administration','','',0,'',0);
INSERT INTO t1 VALUES (23,0,0,'','normal','','2000-03-16 18:58:12',20000321114747,'','','All','P2','CCC/CCCCCC','Other',5,'7.00','DDDDDDDDD','','',0,'',0);
INSERT INTO t1 VALUES (24,0,0,'','normal','','2000-03-17 11:08:10',20000321114747,'','','All','P2','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
INSERT INTO t1 VALUES (25,0,0,'','normal','','2000-03-17 11:10:45',20000321114747,'','','All','P2','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
INSERT INTO t1 VALUES (26,0,0,'','normal','','2000-03-17 11:15:47',20000321114747,'','','All','P2','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
INSERT INTO t1 VALUES (27,0,0,'','normal','','2000-03-17 17:45:41',20000321114747,'','','All','P2','CCC/CCCCCC','PC',5,'7.00','DDDDDDDDD','','',0,'',0);
INSERT INTO t1 VALUES (28,0,0,'','normal','','2000-03-20 09:51:45',20000321114747,'','','Windows NT','P2','TestProduct','PC',8,'other','TestComponent','','',0,'',0);
INSERT INTO t1 VALUES (29,0,0,'','normal','','2000-03-20 11:15:09',20000321114747,'','','All','P5','AAAAAAAA-AAA','PC',3,'2.8','Web Interface','','',0,'',0);
CREATE TABLE t2 (
  value tinytext,
  program varchar(64),
  initialowner tinytext NOT NULL,
  initialqacontact tinytext NOT NULL,
  description mediumtext NOT NULL
);

INSERT INTO t2 VALUES ('TestComponent','TestProduct','id0001','','');
INSERT INTO t2 VALUES ('BBBBBBBBBBBBB - conversion','AAAAA','id0001','','');
INSERT INTO t2 VALUES ('BBBBBBBBBBBBB - generic','AAAAA','id0001','','');
INSERT INTO t2 VALUES ('TestComponent2','TestProduct','id0001','','');
INSERT INTO t2 VALUES ('BBBBBBBBBBBBB - eeeeeeeee','AAAAA','id0001','','');
INSERT INTO t2 VALUES ('kkkkkkkkkkk lllllllllll','AAAAA','id0001','','');
INSERT INTO t2 VALUES ('Test Procedures','AAAAA','id0001','','');
INSERT INTO t2 VALUES ('Documentation','AAAAA','id0003','','');
INSERT INTO t2 VALUES ('DDDDDDDDD','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Eeeeeeee Lite','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Eeeeeeee Full','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Administration','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Distribution','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Setup','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Unspecified','CCC/CCCCCC','id0002','','');
INSERT INTO t2 VALUES ('Web Interface','AAAAAAAA-AAA','id0001','','');
INSERT INTO t2 VALUES ('Host communication','AAAAA','id0001','','');
select value,description,bug_id from t2 left join t1 on t2.program=t1.product and t2.value=t1.component where program="AAAAA";
select value,description,COUNT(bug_id) from t2 left join t1 on t2.program=t1.product and t2.value=t1.component where program="AAAAA" group by value;
select value,description,COUNT(bug_id) from t2 left join t1 on t2.program=t1.product and t2.value=t1.component where program="AAAAA" group by value having COUNT(bug_id) IN (0,2);

drop table t1,t2;

#
# Problem with functions and group functions when no matching rows
#

create table t1 (foo int);
insert into t1 values (1);
select 1+1, "a",count(*) from t1 where foo in (2);
insert into t1 values (1);
select 1+1,"a",count(*) from t1 where foo in (2);
drop table t1;

#
# Test GROUP BY DESC

CREATE TABLE t1 (
  spID int(10) unsigned,
  userID int(10) unsigned,
  score smallint(5) unsigned,
  key (spid),
  key (score)
);

INSERT INTO t1 VALUES (1,1,1),(2,2,2),(2,1,1),(3,3,3),(4,3,3),(5,3,3),(6,3,3),(7,3,3);
explain select userid,count(*) from t1 group by userid desc;
explain select userid,count(*) from t1 group by userid desc order by null;
select userid,count(*) from t1 group by userid desc;
select userid,count(*) from t1 group by userid desc having (count(*)+1) IN (4,3);
select userid,count(*) from t1 group by userid desc having 3  IN (1,COUNT(*));
explain select spid,count(*) from t1 where spid between 1 and 2 group by spid desc;
explain select spid,count(*) from t1 where spid between 1 and 2 group by spid;
explain select spid,count(*) from t1 where spid between 1 and 2 group by spid order by null;
select spid,count(*) from t1 where spid between 1 and 2 group by spid;
select spid,count(*) from t1 where spid between 1 and 2 group by spid desc;
explain extended select sql_big_result spid,sum(userid) from t1 group by spid desc;
explain select sql_big_result spid,sum(userid) from t1 group by spid desc order by null;
select sql_big_result spid,sum(userid) from t1 group by spid desc;
explain select sql_big_result score,count(*) from t1 group by score desc;
explain select sql_big_result score,count(*) from t1 group by score desc order by null;
select sql_big_result score,count(*) from t1 group by score desc;
drop table t1;

# not purely group_by bug, but group_by is involved...

create table t1 (a date default null, b date default null);
insert t1 values ('1999-10-01','2000-01-10'), ('1997-01-01','1998-10-01');
select a,min(b) c,count(distinct rand()) from t1 group by a having c<a + interval 1 day;
drop table t1;

# Compare with hash keys

CREATE TABLE t1 (a char(1));
INSERT INTO t1 VALUES ('A'),('B'),('A'),('B'),('A'),('B'),(NULL),('a'),('b'),(NULL),('A'),('B'),(NULL);
SELECT a FROM t1 GROUP BY a;
SELECT a,count(*) FROM t1 GROUP BY a;
SELECT a FROM t1 GROUP BY binary a;
SELECT a,count(*) FROM t1 GROUP BY binary a;
SELECT binary a FROM t1 GROUP BY 1;
SELECT binary a,count(*) FROM t1 GROUP BY 1;
# Do the same tests with MyISAM temporary tables
SET SQL_BIG_TABLES=1;
SELECT a FROM t1 GROUP BY a;
SELECT a,count(*) FROM t1 GROUP BY a;
SELECT a FROM t1 GROUP BY binary a;
SELECT a,count(*) FROM t1 GROUP BY binary a;
SELECT binary a FROM t1 GROUP BY 1;
SELECT binary a,count(*) FROM t1 GROUP BY 1;
SET SQL_BIG_TABLES=0;
drop table t1;

#
# Test of key >= 256 bytes
#

CREATE TABLE t1 (
  `a` char(193) default NULL,
  `b` char(63) default NULL
);
INSERT INTO t1 VALUES ('abc','def'),('hij','klm');
SELECT CONCAT(a, b) FROM t1 GROUP BY 1;
SELECT CONCAT(a, b),count(*) FROM t1 GROUP BY 1;
SELECT CONCAT(a, b),count(distinct a) FROM t1 GROUP BY 1;
SELECT 1 FROM t1 GROUP BY CONCAT(a, b);
INSERT INTO t1 values ('hij','klm');
SELECT CONCAT(a, b),count(*) FROM t1 GROUP BY 1;
DROP TABLE t1;

#
# Test problem with ORDER BY on a SUM() column
#

create table t1 (One int unsigned, Two int unsigned, Three int unsigned, Four int unsigned);
insert into t1 values (1,2,1,4),(1,2,2,4),(1,2,3,4),(1,2,4,4),(1,1,1,4),(1,1,2,4),(1,1,3,4),(1,1,4,4),(1,3,1,4),(1,3,2,4),(1,3,3,4),(1,3,4,4);
select One, Two, sum(Four) from t1 group by One,Two;
drop table t1;

create table t1 (id integer primary key not null auto_increment, gender char(1));
insert into t1 values (NULL, 'M'), (NULL, 'F'),(NULL, 'F'),(NULL, 'F'),(NULL, 'M');
create table t2 (user_id integer not null, date date);
insert into t2 values (1, '2002-06-09'),(2, '2002-06-09'),(1, '2002-06-09'),(3, '2002-06-09'),(4, '2002-06-09'),(4, '2002-06-09');
select u.gender as gender, count(distinct  u.id) as dist_count, (count(distinct u.id)/5*100) as percentage from t1 u, t2 l where l.user_id = u.id group by u.gender;
select u.gender as  gender, count(distinct  u.id) as dist_count, (count(distinct u.id)/5*100) as percentage from t1 u, t2 l where l.user_id = u.id group by u.gender  order by percentage;
drop table t1,t2;

#
# The GROUP BY returned rows in wrong order in 3.23.51
#

CREATE TABLE t1 (ID1 int, ID2 int, ID int NOT NULL AUTO_INCREMENT,PRIMARY KEY(ID
));
insert into t1 values (1,244,NULL),(2,243,NULL),(134,223,NULL),(185,186,NULL);
select S.ID as xID, S.ID1 as xID1 from t1 as S left join t1 as yS  on S.ID1 between yS.ID1 and yS.ID2;
select S.ID as xID, S.ID1 as xID1, repeat('*',count(distinct yS.ID)) as Level from t1 as S left join t1 as yS  on S.ID1 between yS.ID1 and yS.ID2 group by xID order by xID1;
drop table t1;

#
# Problem with MAX and LEFT JOIN
#

CREATE TABLE t1 (
  pid int(11) unsigned NOT NULL default '0',
  c1id int(11) unsigned default NULL,
  c2id int(11) unsigned default NULL,
  value int(11) unsigned NOT NULL default '0',
  UNIQUE KEY pid2 (pid,c1id,c2id),
  UNIQUE KEY pid (pid,value)
) ENGINE=MyISAM;

INSERT INTO t1 VALUES (1, 1, NULL, 1),(1, 2, NULL, 2),(1, NULL, 3, 3),(1, 4, NULL, 4),(1, 5, NULL, 5);

CREATE TABLE t2 (
  id int(11) unsigned NOT NULL default '0',
  active enum('Yes','No') NOT NULL default 'Yes',
  PRIMARY KEY  (id)
) ENGINE=MyISAM;

INSERT INTO t2 VALUES (1, 'Yes'),(2, 'No'),(4, 'Yes'),(5, 'No');

CREATE TABLE t3 (
  id int(11) unsigned NOT NULL default '0',
  active enum('Yes','No') NOT NULL default 'Yes',
  PRIMARY KEY  (id)
);
INSERT INTO t3 VALUES (3, 'Yes');

select * from t1 AS m LEFT JOIN t2 AS c1 ON m.c1id = 
c1.id AND c1.active = 'Yes' LEFT JOIN t3 AS c2 ON m.c2id = c2.id AND 
c2.active = 'Yes' WHERE m.pid=1  AND (c1.id IS NOT NULL OR c2.id IS NOT NULL);
select max(value) from t1 AS m LEFT JOIN t2 AS c1 ON 
m.c1id = c1.id AND c1.active = 'Yes' LEFT JOIN t3 AS c2 ON m.c2id = 
c2.id AND c2.active = 'Yes' WHERE m.pid=1  AND (c1.id IS NOT NULL OR c2.id IS 
NOT NULL);
drop table t1,t2,t3;

#
# Test bug in GROUP BY on BLOB that is NULL or empty
#

create table t1 (a blob null);
insert into t1 values (NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(""),(""),(""),("b");
select a,count(*) from t1 group by a;
set option sql_big_tables=1;
select a,count(*) from t1 group by a;
drop table t1;

#
# Test of GROUP BY ... ORDER BY NULL optimization
#

create table t1 (a int not null, b int not null);
insert into t1 values (1,1),(1,2),(3,1),(3,2),(2,2),(2,1);
create table t2 (a int not null, b int not null, key(a));
insert into t2 values (1,3),(3,1),(2,2),(1,1);
select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b;
select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b ORDER BY NULL;
explain select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b;
explain select t1.a,t2.b from t1,t2 where t1.a=t2.a group by t1.a,t2.b ORDER BY NULL;
drop table t1,t2;

#
# group function arguments in some functions
#

create table t1 (a int, b int);
insert into t1 values (1, 4),(10, 40),(1, 4),(10, 43),(1, 4),(10, 41),(1, 4),(10, 43),(1, 4);
select a, MAX(b), INTERVAL (MAX(b), 1,3,10,30,39,40,50,60,100,1000) from t1 group by a;
select a, MAX(b), CASE MAX(b) when 4 then 4 when 43 then 43 else 0 end from t1 group by a;
select a, MAX(b), FIELD(MAX(b), '43', '4', '5') from t1 group by a;
select a, MAX(b), CONCAT_WS(MAX(b), '43', '4', '5') from t1 group by a;
select a, MAX(b), ELT(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f') from t1 group by a;
select a, MAX(b), MAKE_SET(MAX(b), 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h') from t1 group by a;
drop table t1;

#
# Problem with group by and alias
#

create table t1 (id int not null, qty int not null);
insert into t1 values (1,2),(1,3),(2,4),(2,5);
select id, sum(qty) as sqty, count(qty) as cqty from t1 group by id having sum(qty)>2 and cqty>1;
select id, sum(qty) as sqty from t1 group by id having sqty>2 and count(qty)>1;
select id, sum(qty) as sqty, count(qty) as cqty from t1 group by id having sqty>2 and cqty>1;
select id, sum(qty) as sqty, count(qty) as cqty from t1 group by id having sum(qty)>2 and count(qty)>1;
select count(*), case interval(qty,2,3,4,5,6,7,8) when -1 then NULL when 0 then "zero" when 1 then "one" when 2 then "two" end as category from t1 group by category;
select count(*), interval(qty,2,3,4,5,6,7,8) as category from t1 group by category;
drop table t1;
#
# Tests for bug #1355: 'Using filesort' is missing in EXPLAIN when ORDER BY
# NULL is used.
#
CREATE TABLE t1 (
  userid int(10) unsigned,
  score smallint(5) unsigned,
  key (score)
);
INSERT INTO t1 VALUES (1,1),(2,2),(1,1),(3,3),(3,3),(3,3),(3,3),(3,3);
# Here we select unordered GROUP BY into a temporary talbe, 
# and then sort it with filesort (GROUP BY in MySQL 
# implies sorted order of results)
SELECT userid,count(*) FROM t1 GROUP BY userid DESC;
EXPLAIN SELECT userid,count(*) FROM t1 GROUP BY userid DESC;
DROP TABLE t1;
CREATE TABLE t1 (
  i int(11) default NULL,
  j int(11) default NULL
);
INSERT INTO t1 VALUES (1,2),(2,3),(4,5),(3,5),(1,5),(23,5);
SELECT i, COUNT(DISTINCT(i)) FROM t1 GROUP BY j ORDER BY NULL;
explain SELECT i, COUNT(DISTINCT(i)) FROM t1 GROUP BY j ORDER BY NULL;
DROP TABLE t1;

#Test for BUG#6976: Aggregate functions have incorrect NULL-ness
create table t1 (a int);
insert into t1 values(null);
select min(a) is null from t1;
select min(a) is null or null from t1;
select 1 and min(a) is null from t1;
drop table t1;

# Test for BUG#5400: GROUP_CONCAT returns everything twice.
create table t1 ( col1 int, col2 int );
insert into t1 values (1,1),(1,2),(1,3),(2,1),(2,2);
select group_concat( distinct col1 ) as alias from t1
  group by col2 having alias like '%';

drop table t1;

#
# Test BUG#8216 when referring in HAVING to n alias which is rand() function
#

create table t1 (a integer, b integer, c integer);
insert into t1 (a,b) values (1,2),(1,3),(2,5);
select a, 0.1*0+1 r2, sum(1) r1 from t1 where a = 1 group  by a having r1>1 and r2=1;
# rand(100)*10 will be < 2 only for the first row (of 6)
select a, round(rand(100)*10) r2, sum(1) r1 from t1 where a = 1 group  by a having r1>1 and r2<=2;
select a,sum(b) from t1 where a=1 group by c;
select a*sum(b) from t1 where a=1 group by c;
select sum(a)*sum(b) from t1 where a=1 group by c;
select a,sum(b) from t1 where a=1 group by c having a=1;
select a as d,sum(b) from t1 where a=1 group by c having d=1;
select sum(a)*sum(b) as d from t1 where a=1 group by c having d > 0;
drop table t1;

# Test for BUG#9213 GROUP BY query on utf-8 key returns wrong results
create table t1(a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(8),(9);
create table t2 (
  a int,
  b varchar(200) NOT NULL,
  c varchar(50) NOT NULL,
  d varchar(100) NOT NULL,
  primary key (a,b(132),c,d),
  key a (a,b)
) charset=utf8;

insert into t2 select 
   x3.a,  -- 3
   concat('val-', x3.a + 3*x4.a), -- 12
   concat('val-', @a:=x3.a + 3*x4.a + 12*C.a), -- 120
   concat('val-', @a + 120*D.a)
from t1 x3, t1 x4, t1 C, t1 D where x3.a < 3 and x4.a < 4 and D.a < 4;

delete from t2  where a = 2 and b = 'val-2' order by a,b,c,d limit 30;

explain select c from t2 where a = 2 and b = 'val-2' group by c;
select c from t2 where a = 2 and b = 'val-2' group by c;
drop table t1,t2;

# Test for BUG#9298 "Wrong handling of int4 unsigned columns in GROUP functions"
# (the actual problem was with protocol code, not GROUP BY)
create table t1 (b int4 unsigned not null);
insert into t1 values(3000000000);
select * from t1;
select min(b) from t1;
drop table t1;

#
# Test for bug #11088: GROUP BY a BLOB column with COUNT(DISTINCT column1) 
#

CREATE TABLE t1 (id int PRIMARY KEY, user_id int, hostname longtext);

INSERT INTO t1 VALUES
  (1, 7, 'cache-dtc-af05.proxy.aol.com'),
  (2, 3, 'what.ever.com'),
  (3, 7, 'cache-dtc-af05.proxy.aol.com'),
  (4, 7, 'cache-dtc-af05.proxy.aol.com');

SELECT hostname, COUNT(DISTINCT user_id) as no FROM t1
  WHERE hostname LIKE '%aol%'
    GROUP BY hostname;

DROP TABLE t1;

#
# Test for bug #8614: GROUP BY 'const' with DISTINCT  
#

CREATE TABLE t1 (a  int, b int);
INSERT INTO t1 VALUES (1,2), (1,3);
SELECT a, b FROM t1 GROUP BY 'const';
SELECT DISTINCT a, b FROM t1 GROUP BY 'const';

DROP TABLE t1;

#
# Test for bug #11385: GROUP BY for datetime converted to decimals  
#

CREATE TABLE t1 (id INT, dt DATETIME);
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
SELECT dt DIV 1 AS f, id FROM t1 GROUP BY f;

DROP TABLE t1;

#
# Test for bug #11295: GROUP BY a BLOB column with COUNT(DISTINCT column1) 
#                      when the BLOB column takes NULL values
# 

CREATE TABLE t1 (id varchar(20) NOT NULL);
INSERT INTO t1 VALUES ('trans1'), ('trans2');
CREATE TABLE t2 (id varchar(20) NOT NULL, err_comment blob NOT NULL);
INSERT INTO t2 VALUES ('trans1', 'a problem');
SELECT COUNT(DISTINCT(t1.id)), LEFT(err_comment, 256) AS comment
  FROM t1 LEFT JOIN t2 ON t1.id=t2.id GROUP BY comment;

DROP TABLE t1, t2;

#
# Bug #12266 GROUP BY expression on DATE column produces result with
#            reduced length
#
create table t1 (f1 date);
insert into t1 values('2005-06-06');
insert into t1 values('2005-06-06'); 
select date(left(f1+0,8)) from t1 group by 1;
drop table t1;

#
# Test for bug #11414: crash on Windows for a simple GROUP BY query 
#  
                    
CREATE TABLE t1 (n int);
INSERT INTO t1 VALUES (1);
SELECT n+1 AS n FROM t1 GROUP BY n;
DROP TABLE t1;

#
# BUG#12695: Item_func_isnull::update_used_tables
# did not update const_item_cache
#
create table t1(f1 varchar(5) key);
insert into t1 values (1),(2);
select sql_buffer_result max(f1) is null from t1;
select sql_buffer_result max(f1)+1 from t1;
drop table t1;

#
# BUG#14019-4.1-opt
#
CREATE TABLE t1(a INT); INSERT INTO t1 VALUES (1),(2);

SELECT a FROM t1 GROUP BY 'a';
SELECT a FROM t1 GROUP BY "a";
SELECT a FROM t1 GROUP BY `a`;

set sql_mode=ANSI_QUOTES;
SELECT a FROM t1 GROUP BY "a";
SELECT a FROM t1 GROUP BY 'a';
SELECT a FROM t1 GROUP BY `a`;
set sql_mode='';

SELECT a FROM t1 HAVING 'a' > 1;
SELECT a FROM t1 HAVING "a" > 1;
SELECT a FROM t1 HAVING `a` > 1;

SELECT a FROM t1 ORDER BY 'a' DESC;
SELECT a FROM t1 ORDER BY "a" DESC;
SELECT a FROM t1 ORDER BY `a` DESC;
DROP TABLE t1;

#
# Bug #29717 INSERT INTO SELECT inserts values even if SELECT statement itself
# returns empty
# 
CREATE TABLE t1 (
    f1 int(10) unsigned NOT NULL auto_increment primary key,
    f2 varchar(100) NOT NULL default ''
);
CREATE TABLE t2 (
    f1 varchar(10) NOT NULL default '',
    f2 char(3) NOT NULL default '',
    PRIMARY KEY  (`f1`),
    KEY `k1` (`f2`,`f1`)
);

INSERT INTO t1 values(NULL, '');
INSERT INTO `t2` VALUES ('486878','WDT'),('486910','WDT');
SELECT SQL_BUFFER_RESULT avg(t2.f1) FROM t1, t2 where t2.f2 = 'SIR' GROUP BY t1.f1;
SELECT avg(t2.f1) FROM t1, t2 where t2.f2 = 'SIR' GROUP BY t1.f1;
DROP TABLE t1, t2;


# End of 4.1 tests

#
# Bug#11211: Ambiguous column reference in GROUP BY.
#

create table t1 (c1 char(3), c2 char(3));
create table t2 (c3 char(3), c4 char(3));
insert into t1 values ('aaa', 'bb1'), ('aaa', 'bb2');
insert into t2 values ('aaa', 'bb1'), ('aaa', 'bb2');

# query with ambiguous column reference 'c2'
select t1.c1 as c2 from t1, t2 where t1.c2 = t2.c4
group by c2;
show warnings;

# this query has no ambiguity
select t1.c1 as c2 from t1, t2 where t1.c2 = t2.c4
group by t1.c1;

show warnings;
drop table t1, t2;

#
# Bug #20466: a view is mixing data when there's a trigger on the table
#
CREATE TABLE t1 (a tinyint(3), b varchar(255), PRIMARY KEY  (a));

INSERT INTO t1 VALUES (1,'-----'), (6,'Allemagne'), (17,'Autriche'), 
    (25,'Belgique'), (54,'Danemark'), (62,'Espagne'), (68,'France');

CREATE TABLE t2 (a tinyint(3), b tinyint(3), PRIMARY KEY  (a), KEY b (b));

INSERT INTO t2 VALUES (1,1), (2,1), (6,6), (18,17), (15,25), (16,25),
 (17,25), (10,54), (5,62),(3,68);

CREATE VIEW v1 AS select t1.a, concat(t1.b,'') AS b, t1.b as real_b from t1;

explain 
SELECT straight_join sql_no_cache v1.a, v1.b, v1.real_b from t2, v1
where t2.b=v1.a GROUP BY t2.b;
SELECT straight_join sql_no_cache v1.a, v1.b, v1.real_b from t2, v1
where t2.b=v1.a GROUP BY t2.b;

DROP VIEW v1;
DROP TABLE t1,t2;

#
# Bug#22781: SQL_BIG_RESULT fails to influence sort plan
#
CREATE TABLE t1 (a INT PRIMARY KEY, b INT, key (b));

INSERT INTO t1 VALUES (1,      1);
INSERT INTO t1 SELECT  a + 1 , MOD(a + 1 , 20) FROM t1;
INSERT INTO t1 SELECT  a + 2 , MOD(a + 2 , 20) FROM t1;
INSERT INTO t1 SELECT  a + 4 , MOD(a + 4 , 20) FROM t1;
INSERT INTO t1 SELECT  a + 8 , MOD(a + 8 , 20) FROM t1;
INSERT INTO t1 SELECT  a + 16, MOD(a + 16, 20) FROM t1;
INSERT INTO t1 SELECT  a + 32, MOD(a + 32, 20) FROM t1;
INSERT INTO t1 SELECT  a + 64, MOD(a + 64, 20) FROM t1;

SELECT MIN(b), MAX(b) from t1;

EXPLAIN SELECT b, sum(1) FROM t1 GROUP BY b;
EXPLAIN SELECT SQL_BIG_RESULT b, sum(1) FROM t1 GROUP BY b;
SELECT b, sum(1) FROM t1 GROUP BY b;
SELECT SQL_BIG_RESULT b, sum(1) FROM t1 GROUP BY b;
DROP TABLE t1;

#
# Bug #23417: Too strict checks against GROUP BY in the ONLY_FULL_GROUP_BY mode
#
CREATE TABLE t1 (a INT PRIMARY KEY, b INT);
INSERT INTO t1 VALUES (1,1),(2,1),(3,2),(4,2),(5,3),(6,3);

SET SQL_MODE = 'ONLY_FULL_GROUP_BY';
SELECT MAX(a)-MIN(a) FROM t1 GROUP BY b;
SELECT CEILING(MIN(a)) FROM t1 GROUP BY b;
SELECT CASE WHEN AVG(a)>=0 THEN 'Positive' ELSE 'Negative' END FROM t1 
 GROUP BY b;
SELECT a + 1 FROM t1 GROUP BY a;
--error ER_WRONG_FIELD_WITH_GROUP 
SELECT a + b FROM t1 GROUP BY b;
SELECT (SELECT t1_outer.a FROM t1 AS t1_inner GROUP BY b LIMIT 1) 
  FROM t1 AS t1_outer;
SELECT 1 FROM t1 as t1_outer GROUP BY a 
  HAVING (SELECT t1_outer.a FROM t1 AS t1_inner GROUP BY b LIMIT 1);
--error ER_WRONG_FIELD_WITH_GROUP 
SELECT (SELECT t1_outer.a FROM t1 AS t1_inner LIMIT 1) 
  FROM t1 AS t1_outer GROUP BY t1_outer.b;
--error ER_BAD_FIELD_ERROR 
SELECT 1 FROM t1 as t1_outer GROUP BY a 
  HAVING (SELECT t1_outer.b FROM t1 AS t1_inner LIMIT 1);
SELECT (SELECT SUM(t1_inner.a) FROM t1 AS t1_inner LIMIT 1) 
  FROM t1 AS t1_outer GROUP BY t1_outer.b;
SELECT (SELECT SUM(t1_inner.a) FROM t1 AS t1_inner GROUP BY t1_inner.b LIMIT 1)
  FROM t1 AS t1_outer;
--error ER_WRONG_FIELD_WITH_GROUP 
SELECT (SELECT SUM(t1_outer.a) FROM t1 AS t1_inner LIMIT 1) 
  FROM t1 AS t1_outer GROUP BY t1_outer.b;

SELECT 1 FROM t1 as t1_outer 
  WHERE (SELECT t1_outer.b FROM t1 AS t1_inner GROUP BY t1_inner.b LIMIT 1);

SELECT b FROM t1 GROUP BY b HAVING CEILING(b) > 0;

SELECT 1 FROM t1 GROUP BY b HAVING b = 2 OR b = 3 OR SUM(a) > 12;
SELECT 1 FROM t1 GROUP BY b HAVING ROW (b,b) = ROW (1,1);

--error ER_BAD_FIELD_ERROR
SELECT 1 FROM t1 GROUP BY b HAVING a = 2;
--error ER_INVALID_GROUP_FUNC_USE
SELECT 1 FROM t1 GROUP BY SUM(b);
--error ER_WRONG_FIELD_WITH_GROUP 
SELECT b FROM t1 AS t1_outer GROUP BY a HAVING t1_outer.a IN 
  (SELECT SUM(t1_inner.b)+t1_outer.b FROM t1 AS t1_inner GROUP BY t1_inner.a
   HAVING SUM(t1_inner.b)+t1_outer.b > 5);
DROP TABLE t1;
SET SQL_MODE = '';
#
# Bug#27874: Non-grouped columns are allowed by * in ONLY_FULL_GROUP_BY mode.
#
SET SQL_MODE = 'ONLY_FULL_GROUP_BY';
create table t1(f1 int, f2 int);
--error 1055
select * from t1 group by f1;
--error 1055
select * from t1 group by f2;
select * from t1 group by f1, f2;
--error 1055
select t1.f1,t.* from t1, t1 t group by 1;
drop table t1;
SET SQL_MODE = '';

#
# Bug #21174: Index degrades sort performance and 
#             optimizer does not honor IGNORE INDEX.
#             a.k.a WL3527.
#
CREATE TABLE t1 (a INT, b INT,
                 PRIMARY KEY (a),
                 KEY i2(a,b));
INSERT INTO t1 VALUES (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8);
INSERT INTO t1 SELECT a + 8,b FROM t1;
INSERT INTO t1 SELECT a + 16,b FROM t1;
INSERT INTO t1 SELECT a + 32,b FROM t1;
INSERT INTO t1 SELECT a + 64,b FROM t1;
INSERT INTO t1 SELECT a + 128,b FROM t1 limit 16;
ANALYZE TABLE t1;
EXPLAIN SELECT a FROM t1 WHERE a < 2;
EXPLAIN SELECT a FROM t1 WHERE a < 2 ORDER BY a;
EXPLAIN SELECT a FROM t1 WHERE a < 2 GROUP BY a;
EXPLAIN SELECT a FROM t1 IGNORE INDEX (PRIMARY,i2);
EXPLAIN SELECT a FROM t1 IGNORE INDEX FOR JOIN (PRIMARY,i2);
EXPLAIN SELECT a FROM t1 IGNORE INDEX FOR GROUP BY (PRIMARY,i2) GROUP BY a;
EXPLAIN SELECT a FROM t1 IGNORE INDEX FOR ORDER BY (PRIMARY,i2) ORDER BY a;
EXPLAIN SELECT a FROM t1 IGNORE INDEX FOR ORDER BY (PRIMARY)
  IGNORE INDEX FOR GROUP BY (i2) GROUP BY a;
EXPLAIN SELECT a FROM t1 IGNORE INDEX (PRIMARY) IGNORE INDEX FOR ORDER BY (i2);
EXPLAIN SELECT a FROM t1 FORCE INDEX (i2);
EXPLAIN SELECT a FROM t1 USE INDEX ();
EXPLAIN SELECT a FROM t1 USE INDEX () USE INDEX (i2);
--error ER_WRONG_USAGE
EXPLAIN SELECT a FROM t1 
  FORCE INDEX (PRIMARY) 
  IGNORE INDEX FOR GROUP BY (i2)
  IGNORE INDEX FOR ORDER BY (i2)
  USE INDEX (i2);
EXPLAIN SELECT a FROM t1 USE INDEX (i2) USE INDEX ();
--error ER_PARSE_ERROR
EXPLAIN SELECT a FROM t1 FORCE INDEX ();
--error ER_PARSE_ERROR
EXPLAIN SELECT a FROM t1 IGNORE INDEX ();
# disable the columns irrelevant to this test here. On some systems 
# without support for large files the rowid is shorter and its size affects 
# the cost calculations. This causes the optimizer to choose loose index
# scan over normal index access.
--replace_column 4 # 7 # 9 # 10 #
EXPLAIN SELECT a FROM t1 USE INDEX FOR JOIN (i2) 
  USE INDEX FOR GROUP BY (i2) GROUP BY a;
EXPLAIN SELECT a FROM t1 FORCE INDEX FOR JOIN (i2) 
  FORCE INDEX FOR GROUP BY (i2) GROUP BY a;
EXPLAIN SELECT a FROM t1 USE INDEX () IGNORE INDEX (i2);
EXPLAIN SELECT a FROM t1 IGNORE INDEX (i2) USE INDEX ();

EXPLAIN SELECT a FROM t1 
  USE INDEX FOR GROUP BY (i2) 
  USE INDEX FOR ORDER BY (i2)
  USE INDEX FOR JOIN (i2);

EXPLAIN SELECT a FROM t1 
  USE INDEX FOR JOIN (i2) 
  USE INDEX FOR JOIN (i2) 
  USE INDEX FOR JOIN (i2,i2);

EXPLAIN SELECT 1 FROM t1 WHERE a IN
  (SELECT a FROM t1 USE INDEX (i2) IGNORE INDEX (i2));

CREATE TABLE t2 (a INT, b INT, KEY(a));
INSERT INTO t2 VALUES (1, 1), (2, 2), (3,3), (4,4);
EXPLAIN SELECT a, SUM(b) FROM t2 GROUP BY a LIMIT 2; 
EXPLAIN SELECT a, SUM(b) FROM t2 IGNORE INDEX (a) GROUP BY a LIMIT 2;

EXPLAIN SELECT 1 FROM t2 WHERE a IN
  (SELECT a FROM t1 USE INDEX (i2) IGNORE INDEX (i2));

SHOW VARIABLES LIKE 'old';  
--error ER_INCORRECT_GLOBAL_LOCAL_VAR
SET @@old = off;  

DROP TABLE t1, t2;

#
# Bug#30596: GROUP BY optimization gives wrong result order
#
CREATE TABLE t1(
  a INT, 
  b INT NOT NULL, 
  c INT NOT NULL, 
  d INT, 
  UNIQUE KEY (c,b)
);

INSERT INTO t1 VALUES (1,1,1,50), (1,2,3,40), (2,1,3,4);

CREATE TABLE t2(
  a INT,
  b INT,
  UNIQUE KEY(a,b)
);

INSERT INTO t2 VALUES (NULL, NULL), (NULL, NULL), (NULL, 1), (1, NULL), (1, 1), (1,2);

EXPLAIN SELECT c,b,d FROM t1 GROUP BY c,b,d;
SELECT c,b,d FROM t1 GROUP BY c,b,d;
EXPLAIN SELECT c,b,d FROM t1 GROUP BY c,b,d ORDER BY NULL;
SELECT c,b,d FROM t1 GROUP BY c,b,d ORDER BY NULL;
EXPLAIN SELECT c,b,d FROM t1 ORDER BY c,b,d;
SELECT c,b,d FROM t1 ORDER BY c,b,d;

EXPLAIN SELECT c,b,d FROM t1 GROUP BY c,b;
SELECT c,b,d FROM t1 GROUP BY c,b;
EXPLAIN SELECT c,b   FROM t1 GROUP BY c,b;
SELECT c,b   FROM t1 GROUP BY c,b;

EXPLAIN SELECT a,b from t2 ORDER BY a,b;
SELECT a,b from t2 ORDER BY a,b;
EXPLAIN SELECT a,b from t2 GROUP BY a,b;
SELECT a,b from t2 GROUP BY a,b;
EXPLAIN SELECT a from t2 GROUP BY a;
SELECT a from t2 GROUP BY a;
EXPLAIN SELECT b from t2 GROUP BY b;
SELECT b from t2 GROUP BY b;

DROP TABLE t1;