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|
drop table if exists t1, t2, t3;
CREATE TABLE t1 (
event_date date DEFAULT '0000-00-00' NOT NULL,
type int(11) DEFAULT '0' NOT NULL,
event_id int(11) DEFAULT '0' NOT NULL,
PRIMARY KEY (event_date,type,event_id)
);
INSERT INTO t1 VALUES ('1999-07-10',100100,24), ('1999-07-11',100100,25),
('1999-07-13',100600,0), ('1999-07-13',100600,4), ('1999-07-13',100600,26),
('1999-07-14',100600,10), ('1999-07-15',100600,16), ('1999-07-15',100800,45),
('1999-07-15',101000,47), ('1999-07-16',100800,46), ('1999-07-20',100600,5),
('1999-07-20',100600,27), ('1999-07-21',100600,11), ('1999-07-22',100600,17),
('1999-07-23',100100,39), ('1999-07-24',100100,39), ('1999-07-24',100500,40),
('1999-07-25',100100,39), ('1999-07-27',100600,1), ('1999-07-27',100600,6),
('1999-07-27',100600,28), ('1999-07-28',100600,12), ('1999-07-29',100500,41),
('1999-07-29',100600,18), ('1999-07-30',100500,41), ('1999-07-31',100500,41),
('1999-08-01',100700,34), ('1999-08-03',100600,7), ('1999-08-03',100600,29),
('1999-08-04',100600,13), ('1999-08-05',100500,42), ('1999-08-05',100600,19),
('1999-08-06',100500,42), ('1999-08-07',100500,42), ('1999-08-08',100500,42),
('1999-08-10',100600,2), ('1999-08-10',100600,9), ('1999-08-10',100600,30),
('1999-08-11',100600,14), ('1999-08-12',100600,20), ('1999-08-17',100500,8),
('1999-08-17',100600,31), ('1999-08-18',100600,15), ('1999-08-19',100600,22),
('1999-08-24',100600,3), ('1999-08-24',100600,32), ('1999-08-27',100500,43),
('1999-08-31',100600,33), ('1999-09-17',100100,37), ('1999-09-18',100100,37),
('1999-09-19',100100,37), ('2000-12-18',100700,38);
select event_date,type,event_id from t1 WHERE event_date >= "1999-07-01" AND event_date < "1999-07-15" AND (type=100600 OR type=100100) ORDER BY event_date;
event_date type event_id
1999-07-10 100100 24
1999-07-11 100100 25
1999-07-13 100600 0
1999-07-13 100600 4
1999-07-13 100600 26
1999-07-14 100600 10
explain select event_date,type,event_id from t1 WHERE type = 100601 and event_date >= "1999-07-01" AND event_date < "1999-07-15" AND (type=100600 OR type=100100) ORDER BY event_date;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
select event_date,type,event_id from t1 WHERE event_date >= "1999-07-01" AND event_date <= "1999-07-15" AND (type=100600 OR type=100100) or event_date >= "1999-07-01" AND event_date <= "1999-07-15" AND type=100099;
event_date type event_id
1999-07-10 100100 24
1999-07-11 100100 25
1999-07-13 100600 0
1999-07-13 100600 4
1999-07-13 100600 26
1999-07-14 100600 10
1999-07-15 100600 16
drop table t1;
CREATE TABLE t1 (
PAPER_ID smallint(6) DEFAULT '0' NOT NULL,
YEAR smallint(6) DEFAULT '0' NOT NULL,
ISSUE smallint(6) DEFAULT '0' NOT NULL,
CLOSED tinyint(4) DEFAULT '0' NOT NULL,
ISS_DATE date DEFAULT '0000-00-00' NOT NULL,
PRIMARY KEY (PAPER_ID,YEAR,ISSUE)
);
INSERT INTO t1 VALUES (3,1999,34,0,'1999-07-12'), (1,1999,111,0,'1999-03-23'),
(1,1999,222,0,'1999-03-23'), (3,1999,33,0,'1999-07-12'),
(3,1999,32,0,'1999-07-12'), (3,1999,31,0,'1999-07-12'),
(3,1999,30,0,'1999-07-12'), (3,1999,29,0,'1999-07-12'),
(3,1999,28,0,'1999-07-12'), (1,1999,40,1,'1999-05-01'),
(1,1999,41,1,'1999-05-01'), (1,1999,42,1,'1999-05-01'),
(1,1999,46,1,'1999-05-01'), (1,1999,47,1,'1999-05-01'),
(1,1999,48,1,'1999-05-01'), (1,1999,49,1,'1999-05-01'),
(1,1999,50,0,'1999-05-01'), (1,1999,51,0,'1999-05-01'),
(1,1999,200,0,'1999-06-28'), (1,1999,52,0,'1999-06-28'),
(1,1999,53,0,'1999-06-28'), (1,1999,54,0,'1999-06-28'),
(1,1999,55,0,'1999-06-28'), (1,1999,56,0,'1999-07-01'),
(1,1999,57,0,'1999-07-01'), (1,1999,58,0,'1999-07-01'),
(1,1999,59,0,'1999-07-01'), (1,1999,60,0,'1999-07-01'),
(3,1999,35,0,'1999-07-12');
select YEAR,ISSUE from t1 where PAPER_ID=3 and (YEAR>1999 or (YEAR=1999 and ISSUE>28)) order by YEAR,ISSUE;
YEAR ISSUE
1999 29
1999 30
1999 31
1999 32
1999 33
1999 34
1999 35
check table t1;
Table Op Msg_type Msg_text
test.t1 check status OK
repair table t1;
Table Op Msg_type Msg_text
test.t1 repair status OK
drop table t1;
CREATE TABLE t1 (
id int(11) NOT NULL auto_increment,
parent_id int(11) DEFAULT '0' NOT NULL,
level tinyint(4) DEFAULT '0' NOT NULL,
PRIMARY KEY (id),
KEY parent_id (parent_id),
KEY level (level)
);
INSERT INTO t1 VALUES (1,0,0), (3,1,1), (4,1,1), (8,2,2), (9,2,2), (17,3,2),
(22,4,2), (24,4,2), (28,5,2), (29,5,2), (30,5,2), (31,6,2), (32,6,2), (33,6,2),
(203,7,2), (202,7,2), (20,3,2), (157,0,0), (193,5,2), (40,7,2), (2,1,1),
(15,2,2), (6,1,1), (34,6,2), (35,6,2), (16,3,2), (7,1,1), (36,7,2), (18,3,2),
(26,5,2), (27,5,2), (183,4,2), (38,7,2), (25,5,2), (37,7,2), (21,4,2),
(19,3,2), (5,1,1), (179,5,2);
SELECT * FROM t1 WHERE level = 1 AND parent_id = 1;
id parent_id level
3 1 1
4 1 1
2 1 1
6 1 1
7 1 1
5 1 1
SELECT * FROM t1 WHERE level = 1 AND parent_id = 1 order by id;
id parent_id level
2 1 1
3 1 1
4 1 1
5 1 1
6 1 1
7 1 1
drop table t1;
create table t1(
Satellite varchar(25) not null,
SensorMode varchar(25) not null,
FullImageCornersUpperLeftLongitude double not null,
FullImageCornersUpperRightLongitude double not null,
FullImageCornersUpperRightLatitude double not null,
FullImageCornersLowerRightLatitude double not null,
index two (Satellite, SensorMode, FullImageCornersUpperLeftLongitude, FullImageCornersUpperRightLongitude, FullImageCornersUpperRightLatitude, FullImageCornersLowerRightLatitude));
insert into t1 values("OV-3","PAN1",91,-92,40,50);
insert into t1 values("OV-4","PAN1",91,-92,40,50);
select * from t1 where t1.Satellite = "OV-3" and t1.SensorMode = "PAN1" and t1.FullImageCornersUpperLeftLongitude > -90.000000 and t1.FullImageCornersUpperRightLongitude < -82.000000;
Satellite SensorMode FullImageCornersUpperLeftLongitude FullImageCornersUpperRightLongitude FullImageCornersUpperRightLatitude FullImageCornersLowerRightLatitude
OV-3 PAN1 91 -92 40 50
drop table t1;
create table t1 ( aString char(100) not null default "", key aString (aString(10)) );
insert t1 (aString) values ( "believe in myself" ), ( "believe" ), ("baaa" ), ( "believe in love");
select * from t1 where aString < "believe in myself" order by aString;
aString
baaa
believe
believe in love
select * from t1 where aString > "believe in love" order by aString;
aString
believe in myself
alter table t1 drop key aString;
select * from t1 where aString < "believe in myself" order by aString;
aString
baaa
believe
believe in love
select * from t1 where aString > "believe in love" order by aString;
aString
believe in myself
drop table t1;
CREATE TABLE t1 (
t1ID int(10) unsigned NOT NULL auto_increment,
art binary(1) NOT NULL default '',
KNR char(5) NOT NULL default '',
RECHNR char(6) NOT NULL default '',
POSNR char(2) NOT NULL default '',
ARTNR char(10) NOT NULL default '',
TEX char(70) NOT NULL default '',
PRIMARY KEY (t1ID),
KEY IdxArt (art),
KEY IdxKnr (KNR),
KEY IdxArtnr (ARTNR)
) ENGINE=MyISAM;
INSERT INTO t1 (art) VALUES ('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),('j'),('J'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),
('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j'),('j');
select count(*) from t1 where upper(art) = 'J';
count(*)
213
select count(*) from t1 where art = 'J' or art = 'j';
count(*)
602
select count(*) from t1 where art = 'j' or art = 'J';
count(*)
602
select count(*) from t1 where art = 'j';
count(*)
389
select count(*) from t1 where art = 'J';
count(*)
213
drop table t1;
create table t1 (x int, y int, index(x), index(y));
insert into t1 (x) values (1),(2),(3),(4),(5),(6),(7),(8),(9);
update t1 set y=x;
explain select * from t1, t1 t2 where t1.y = 8 and t2.x between 7 and t1.y+0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 2 Using where
explain select * from t1, t1 t2 where t1.y = 8 and t2.x >= 7 and t2.x <= t1.y+0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 2 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between t1.y-1 and t1.y+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 3 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= t1.y-1 and t2.x <= t1.y+1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 3 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x between 0 and t1.y;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 2 Using where
explain select * from t1, t1 t2 where t1.y = 2 and t2.x >= 0 and t2.x <= t1.y;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref y y 5 const 1 Using where
1 SIMPLE t2 range x x 5 NULL 2 Using where
explain select count(*) from t1 where x in (1);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref x x 5 const 1 Using where; Using index
explain select count(*) from t1 where x in (1,2);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index x x 5 NULL 9 Using where; Using index
drop table t1;
CREATE TABLE t1 (key1 int(11) NOT NULL default '0', KEY i1 (key1));
INSERT INTO t1 VALUES (0),(0),(0),(0),(0),(1),(1);
CREATE TABLE t2 (keya int(11) NOT NULL default '0', KEY j1 (keya));
INSERT INTO t2 VALUES (0),(0),(1),(1),(2),(2);
explain select * from t1, t2 where (t1.key1 <t2.keya + 1) and t2.keya=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref j1 j1 4 const 1 Using index
1 SIMPLE t1 index i1 i1 4 NULL 7 Using where; Using index
explain select * from t1 force index(i1), t2 force index(j1) where
(t1.key1 <t2.keya + 1) and t2.keya=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref j1 j1 4 const 1 Using index
1 SIMPLE t1 index i1 i1 4 NULL 7 Using where; Using index
DROP TABLE t1,t2;
CREATE TABLE t1 (
a int(11) default NULL,
b int(11) default NULL,
KEY a (a),
KEY b (b)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES
(1,1),(2,1),(3,1),(4,1),(5,1),(6,1),(7,1),(8,1),(9,1),(10,2),(10,2),
(13,2),(14,2),(15,2),(16,2),(17,3),(17,3),(16,3),(17,3),(19,3),(20,3),
(21,4),(22,5),(23,5),(24,5),(25,5),(26,5),(30,5),(31,5),(32,5),(33,5),
(33,5),(33,5),(33,5),(33,5),(34,5),(35,5);
EXPLAIN SELECT * FROM t1 WHERE a IN(1,2) AND b=5;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a,b a 5 NULL 2 Using where
SELECT * FROM t1 WHERE a IN(1,2) AND b=5;
a b
DROP TABLE t1;
CREATE TABLE t1 (a int, b int, c int, INDEX (c,a,b));
INSERT INTO t1 VALUES (1,0,0),(1,0,0),(1,0,0);
INSERT INTO t1 VALUES (0,1,0),(0,1,0),(0,1,0);
SELECT COUNT(*) FROM t1 WHERE (c=0 and a=1) or (c=0 and b=1);
COUNT(*)
6
SELECT COUNT(*) FROM t1 WHERE (c=0 and b=1) or (c=0 and a=1);
COUNT(*)
6
DROP TABLE t1;
CREATE TABLE t1 ( a int not null, b int not null, INDEX ab(a,b) );
INSERT INTO t1 VALUES (47,1), (70,1), (15,1), (15, 4);
SELECT * FROM t1
WHERE
(
( b =1 AND a BETWEEN 14 AND 21 ) OR
( b =2 AND a BETWEEN 16 AND 18 ) OR
( b =3 AND a BETWEEN 15 AND 19 ) OR
(a BETWEEN 19 AND 47)
);
a b
15 1
47 1
DROP TABLE t1;
CREATE TABLE t1 (
id int( 11 ) unsigned NOT NULL AUTO_INCREMENT ,
line int( 5 ) unsigned NOT NULL default '0',
columnid int( 3 ) unsigned NOT NULL default '0',
owner int( 3 ) unsigned NOT NULL default '0',
ordinal int( 3 ) unsigned NOT NULL default '0',
showid smallint( 6 ) unsigned NOT NULL default '1',
tableid int( 1 ) unsigned NOT NULL default '1',
content int( 5 ) unsigned NOT NULL default '188',
PRIMARY KEY ( owner, id ) ,
KEY menu( owner, showid, columnid ) ,
KEY `COLUMN` ( owner, columnid, line ) ,
KEY `LINES` ( owner, tableid, content, id ) ,
KEY recount( owner, line )
) ENGINE = MYISAM;
INSERT into t1 (owner,id,columnid,line) values (11,15,15,1),(11,13,13,5);
SELECT id, columnid, tableid, content, showid, line, ordinal FROM t1 WHERE owner=11 AND ((columnid IN ( 15, 13, 14 ) AND line IN ( 1, 2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 31 )) OR (columnid IN ( 13, 14 ) AND line IN ( 15 ))) LIMIT 0 , 30;
id columnid tableid content showid line ordinal
13 13 1 188 1 5 0
15 15 1 188 1 1 0
drop table t1;
create table t1 (id int(10) primary key);
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9);
select id from t1 where id in (2,5,9) ;
id
2
5
9
select id from t1 where id=2 or id=5 or id=9 ;
id
2
5
9
drop table t1;
create table t1 ( id1 int not null, id2 int not null, idnull int null, c char(20), primary key (id1,id2));
insert into t1 values (0,1,NULL,"aaa"), (1,1,NULL,"aaa"), (2,1,NULL,"aaa"),
(3,1,NULL,"aaa"), (4,1,NULL,"aaa"), (5,1,NULL,"aaa"),
(6,1,NULL,"aaa"), (7,1,NULL,"aaa"), (8,1,NULL,"aaa"),
(9,1,NULL,"aaa"), (10,1,NULL,"aaa"), (11,1,NULL,"aaa"),
(12,1,NULL,"aaa"), (13,1,NULL,"aaa"), (14,1,NULL,"aaa"),
(15,1,NULL,"aaa"), (16,1,NULL,"aaa"), (17,1,NULL,"aaa"),
(18,1,NULL,"aaa"), (19,1,NULL,"aaa"), (20,1,NULL,"aaa");
select a.id1, b.idnull from t1 as a, t1 as b where a.id2=1 and a.id1=1 and b.id1=a.idnull order by b.id2 desc limit 1;
id1 idnull
drop table t1;
create table t1 (
id int not null auto_increment,
name char(1) not null,
uid int not null,
primary key (id),
index uid_index (uid));
create table t2 (
id int not null auto_increment,
name char(1) not null,
uid int not null,
primary key (id),
index uid_index (uid));
insert into t1(id, uid, name) values(1, 0, ' ');
insert into t1(uid, name) values(0, ' ');
insert into t2(uid, name) select uid, name from t1;
insert into t1(uid, name) select uid, name from t2;
insert into t2(uid, name) select uid, name from t1;
insert into t1(uid, name) select uid, name from t2;
insert into t2(uid, name) select uid, name from t1;
insert into t1(uid, name) select uid, name from t2;
insert into t2(uid, name) select uid, name from t1;
insert into t1(uid, name) select uid, name from t2;
insert into t2(uid, name) select uid, name from t1;
insert into t1(uid, name) select uid, name from t2;
insert into t2(uid, name) select uid, name from t1;
insert into t2(uid, name) select uid, name from t1;
insert into t2(uid, name) select uid, name from t1;
insert into t2(uid, name) select uid, name from t1;
insert into t1(uid, name) select uid, name from t2;
delete from t2;
insert into t2(uid, name) values
(1, CHAR(64+1)),
(2, CHAR(64+2)),
(3, CHAR(64+3)),
(4, CHAR(64+4)),
(5, CHAR(64+5)),
(6, CHAR(64+6)),
(7, CHAR(64+7)),
(8, CHAR(64+8)),
(9, CHAR(64+9)),
(10, CHAR(64+10)),
(11, CHAR(64+11)),
(12, CHAR(64+12)),
(13, CHAR(64+13)),
(14, CHAR(64+14)),
(15, CHAR(64+15)),
(16, CHAR(64+16)),
(17, CHAR(64+17)),
(18, CHAR(64+18)),
(19, CHAR(64+19)),
(20, CHAR(64+20)),
(21, CHAR(64+21)),
(22, CHAR(64+22)),
(23, CHAR(64+23)),
(24, CHAR(64+24)),
(25, CHAR(64+25)),
(26, CHAR(64+26));
insert into t1(uid, name) select uid, name from t2;
delete from t2;
insert into t2(id, uid, name) select id, uid, name from t1;
select count(*) from t1;
count(*)
1026
select count(*) from t2;
count(*)
1026
analyze table t1,t2;
Table Op Msg_type Msg_text
test.t1 analyze status OK
test.t2 analyze status Table is already up to date
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 112 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid > 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 112 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t1.uid != 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 113 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
explain select * from t1, t2 where t1.uid=t2.uid AND t2.uid != 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range uid_index uid_index 4 NULL 113 Using where
1 SIMPLE t2 ref uid_index uid_index 4 test.t1.uid 38
select * from t1, t2 where t1.uid=t2.uid AND t1.uid > 0;
id name uid id name uid
1001 A 1 1001 A 1
1002 B 2 1002 B 2
1003 C 3 1003 C 3
1004 D 4 1004 D 4
1005 E 5 1005 E 5
1006 F 6 1006 F 6
1007 G 7 1007 G 7
1008 H 8 1008 H 8
1009 I 9 1009 I 9
1010 J 10 1010 J 10
1011 K 11 1011 K 11
1012 L 12 1012 L 12
1013 M 13 1013 M 13
1014 N 14 1014 N 14
1015 O 15 1015 O 15
1016 P 16 1016 P 16
1017 Q 17 1017 Q 17
1018 R 18 1018 R 18
1019 S 19 1019 S 19
1020 T 20 1020 T 20
1021 U 21 1021 U 21
1022 V 22 1022 V 22
1023 W 23 1023 W 23
1024 X 24 1024 X 24
1025 Y 25 1025 Y 25
1026 Z 26 1026 Z 26
select * from t1, t2 where t1.uid=t2.uid AND t1.uid != 0;
id name uid id name uid
1001 A 1 1001 A 1
1002 B 2 1002 B 2
1003 C 3 1003 C 3
1004 D 4 1004 D 4
1005 E 5 1005 E 5
1006 F 6 1006 F 6
1007 G 7 1007 G 7
1008 H 8 1008 H 8
1009 I 9 1009 I 9
1010 J 10 1010 J 10
1011 K 11 1011 K 11
1012 L 12 1012 L 12
1013 M 13 1013 M 13
1014 N 14 1014 N 14
1015 O 15 1015 O 15
1016 P 16 1016 P 16
1017 Q 17 1017 Q 17
1018 R 18 1018 R 18
1019 S 19 1019 S 19
1020 T 20 1020 T 20
1021 U 21 1021 U 21
1022 V 22 1022 V 22
1023 W 23 1023 W 23
1024 X 24 1024 X 24
1025 Y 25 1025 Y 25
1026 Z 26 1026 Z 26
drop table t1,t2;
create table t1 (x bigint unsigned not null);
insert into t1(x) values (0xfffffffffffffff0);
insert into t1(x) values (0xfffffffffffffff1);
select * from t1;
x
18446744073709551600
18446744073709551601
select count(*) from t1 where x>0;
count(*)
2
select count(*) from t1 where x=0;
count(*)
0
select count(*) from t1 where x<0;
count(*)
0
select count(*) from t1 where x < -16;
count(*)
0
select count(*) from t1 where x = -16;
count(*)
0
select count(*) from t1 where x > -16;
count(*)
2
select count(*) from t1 where x = 18446744073709551601;
count(*)
1
create table t2 (x bigint not null);
insert into t2(x) values (cast(0xfffffffffffffff0+0 as signed));
insert into t2(x) values (cast(0xfffffffffffffff1+0 as signed));
select * from t2;
x
-16
-15
select count(*) from t2 where x>0;
count(*)
0
select count(*) from t2 where x=0;
count(*)
0
select count(*) from t2 where x<0;
count(*)
2
select count(*) from t2 where x < -16;
count(*)
0
select count(*) from t2 where x = -16;
count(*)
1
select count(*) from t2 where x > -16;
count(*)
1
select count(*) from t2 where x = 18446744073709551601;
count(*)
0
drop table t1,t2;
create table t1 (x bigint unsigned not null primary key) engine=innodb;
insert into t1(x) values (0xfffffffffffffff0);
insert into t1(x) values (0xfffffffffffffff1);
select * from t1;
x
18446744073709551600
18446744073709551601
select count(*) from t1 where x>0;
count(*)
2
select count(*) from t1 where x=0;
count(*)
0
select count(*) from t1 where x<0;
count(*)
0
select count(*) from t1 where x < -16;
count(*)
0
select count(*) from t1 where x = -16;
count(*)
0
select count(*) from t1 where x > -16;
count(*)
2
select count(*) from t1 where x = 18446744073709551601;
count(*)
1
drop table t1;
create table t1 (a bigint unsigned);
create index t1i on t1(a);
insert into t1 select 18446744073709551615;
insert into t1 select 18446744073709551614;
explain select * from t1 where a <> -1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index t1i t1i 9 NULL 2 Using where; Using index
select * from t1 where a <> -1;
a
18446744073709551614
18446744073709551615
explain select * from t1 where a > -1 or a < -1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index t1i t1i 9 NULL 2 Using where; Using index
select * from t1 where a > -1 or a < -1;
a
18446744073709551614
18446744073709551615
explain select * from t1 where a > -1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index t1i t1i 9 NULL 2 Using where; Using index
select * from t1 where a > -1;
a
18446744073709551614
18446744073709551615
explain select * from t1 where a < -1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
select * from t1 where a < -1;
a
drop table t1;
set names latin1;
create table t1 (a char(10), b text, key (a)) character set latin1;
INSERT INTO t1 (a) VALUES
('111'),('222'),('222'),('222'),('222'),('444'),('aaa'),('AAA'),('bbb');
explain select * from t1 where a='aaa';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref a a 11 const 2 Using where
explain select * from t1 where a=binary 'aaa';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 11 NULL 2 Using where
explain select * from t1 where a='aaa' collate latin1_bin;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 11 NULL 2 Using where
explain select * from t1 where a='aaa' collate latin1_german1_ci;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL a NULL NULL NULL 9 Using where
drop table t1;
CREATE TABLE t1 (
`CLIENT` char(3) character set latin1 collate latin1_bin NOT NULL default '000',
`ARG1` char(3) character set latin1 collate latin1_bin NOT NULL default '',
`ARG2` char(3) character set latin1 collate latin1_bin NOT NULL default '',
`FUNCTION` varchar(10) character set latin1 collate latin1_bin NOT NULL default '',
`FUNCTINT` int(11) NOT NULL default '0',
KEY `VERI_CLNT~2` (`ARG1`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
INSERT INTO t1 VALUES ('000',' 0',' 0','Text 001',0), ('000',' 0',' 1','Text 002',0),
('000',' 1',' 2','Text 003',0), ('000',' 2',' 3','Text 004',0),
('001',' 3',' 0','Text 017',0);
SELECT count(*) FROM t1 WHERE CLIENT='000' AND (ARG1 != ' 1' OR ARG1 != ' 2');
count(*)
4
SELECT count(*) FROM t1 WHERE CLIENT='000' AND (ARG1 != ' 2' OR ARG1 != ' 1');
count(*)
4
drop table t1;
create table t1 (a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
CREATE TABLE t2 (
pk1 int(11) NOT NULL,
pk2 int(11) NOT NULL,
pk3 int(11) NOT NULL,
pk4 int(11) NOT NULL,
filler char(82),
PRIMARY KEY (pk1,pk2,pk3,pk4)
) DEFAULT CHARSET=latin1;
insert into t2 select 1, A.a+10*B.a, 432, 44, 'fillerZ' from t1 A, t1 B;
INSERT INTO t2 VALUES (2621, 2635, 0, 0,'filler'), (2621, 2635, 1, 0,'filler'),
(2621, 2635, 10, 0,'filler'), (2621, 2635, 11, 0,'filler'),
(2621, 2635, 14, 0,'filler'), (2621, 2635, 1000015, 0,'filler');
SELECT * FROM t2
WHERE ((((pk4 =0) AND (pk1 =2621) AND (pk2 =2635)))
OR ((pk4 =1) AND (((pk1 IN ( 7, 2, 1 ))) OR (pk1 =522)) AND ((pk2 IN ( 0, 2635))))
) AND (pk3 >=1000000);
pk1 pk2 pk3 pk4 filler
2621 2635 1000015 0 filler
drop table t1, t2;
CREATE TABLE t1 (
id int(11) NOT NULL auto_increment,
status varchar(20),
PRIMARY KEY (id),
KEY (status)
);
INSERT INTO t1 VALUES
(1,'B'), (2,'B'), (3,'B'), (4,'B'), (5,'B'), (6,'B'),
(7,'B'), (8,'B'), (9,'B'), (10,'B'), (11,'B'), (12,'B'),
(13,'B'), (14,'B'), (15,'B'), (16,'B'), (17,'B'), (18,'B'),
(19,'B'), (20,'B'), (21,'B'), (22,'B'), (23,'B'), (24,'B'),
(25,'A'), (26,'A'), (27,'A'), (28,'A'), (29,'A'), (30,'A'),
(31,'A'), (32,'A'), (33,'A'), (34,'A'), (35,'A'), (36,'A'),
(37,'A'), (38,'A'), (39,'A'), (40,'A'), (41,'A'), (42,'A'),
(43,'A'), (44,'A'), (45,'A'), (46,'A'), (47,'A'), (48,'A'),
(49,'A'), (50,'A'), (51,'A'), (52,'A'), (53,'C'), (54,'C'),
(55,'C'), (56,'C'), (57,'C'), (58,'C'), (59,'C'), (60,'C');
EXPLAIN SELECT * FROM t1 WHERE status <> 'A' AND status <> 'B';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range status status 23 NULL 11 Using where
EXPLAIN SELECT * FROM t1 WHERE status NOT IN ('A','B');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range status status 23 NULL 11 Using where
SELECT * FROM t1 WHERE status <> 'A' AND status <> 'B';
id status
53 C
54 C
55 C
56 C
57 C
58 C
59 C
60 C
SELECT * FROM t1 WHERE status NOT IN ('A','B');
id status
53 C
54 C
55 C
56 C
57 C
58 C
59 C
60 C
EXPLAIN SELECT status FROM t1 WHERE status <> 'A' AND status <> 'B';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range status status 23 NULL 11 Using where; Using index
EXPLAIN SELECT status FROM t1 WHERE status NOT IN ('A','B');
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range status status 23 NULL 11 Using where; Using index
EXPLAIN SELECT * FROM t1 WHERE status NOT BETWEEN 'A' AND 'B';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range status status 23 NULL 10 Using where
EXPLAIN SELECT * FROM t1 WHERE status < 'A' OR status > 'B';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range status status 23 NULL 10 Using where
SELECT * FROM t1 WHERE status NOT BETWEEN 'A' AND 'B';
id status
53 C
54 C
55 C
56 C
57 C
58 C
59 C
60 C
SELECT * FROM t1 WHERE status < 'A' OR status > 'B';
id status
53 C
54 C
55 C
56 C
57 C
58 C
59 C
60 C
DROP TABLE t1;
CREATE TABLE t1 (a int, b int, primary key(a,b));
INSERT INTO t1 VALUES
(1,1),(1,2),(1,3),(2,1),(2,2),(2,3),(3,1),(3,2),(3,3),(4,1),(4,2),(4,3);
CREATE VIEW v1 as SELECT a,b FROM t1 WHERE b=3;
EXPLAIN SELECT a,b FROM t1 WHERE a < 2 and b=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 4 Using where; Using index
EXPLAIN SELECT a,b FROM v1 WHERE a < 2 and b=3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 4 Using where; Using index
EXPLAIN SELECT a,b FROM t1 WHERE a < 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 4 Using where; Using index
EXPLAIN SELECT a,b FROM v1 WHERE a < 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 4 NULL 4 Using where; Using index
SELECT a,b FROM t1 WHERE a < 2 and b=3;
a b
1 3
SELECT a,b FROM v1 WHERE a < 2 and b=3;
a b
1 3
DROP VIEW v1;
DROP TABLE t1;
CREATE TABLE t1 (name varchar(15) NOT NULL, KEY idx(name));
INSERT INTO t1 VALUES ('Betty'), ('Anna');
SELECT * FROM t1;
name
Anna
Betty
DELETE FROM t1 WHERE name NOT LIKE 'A%a';
SELECT * FROM t1;
name
Anna
DROP TABLE t1;
CREATE TABLE t1 (a int, KEY idx(a));
INSERT INTO t1 VALUES (NULL), (1), (2), (3);
SELECT * FROM t1;
a
NULL
1
2
3
DELETE FROM t1 WHERE NOT(a <=> 2);
SELECT * FROM t1;
a
2
DROP TABLE t1;
create table t1 (a int, b int, primary key(a,b));
create view v1 as select a, b from t1;
INSERT INTO `t1` VALUES
(0,0),(1,0),(2,0),(3,0),(4,0),(5,1),(6,1),(7,1),(8,1),(9,1),(10,2),(11,2),(12,2)
,(13,2),(14,2),(15,3),(16,3),(17,3),(18,3),(19,3);
explain select * from t1 where a in (3,4) and b in (1,2,3);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 8 NULL # Using where; Using index
explain select * from v1 where a in (3,4) and b in (1,2,3);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 8 NULL # Using where; Using index
explain select * from t1 where a between 3 and 4 and b between 1 and 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 8 NULL # Using where; Using index
explain select * from v1 where a between 3 and 4 and b between 1 and 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 8 NULL # Using where; Using index
drop view v1;
drop table t1;
create table t3 (a int);
insert into t3 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t1 (a varchar(10), filler char(200), key(a)) charset=binary;
insert into t1 values ('a','');
insert into t1 values ('a ','');
insert into t1 values ('a ', '');
insert into t1 select concat('a', 1000 + A.a + 10 * (B.a + 10 * C.a)), ''
from t3 A, t3 B, t3 C;
create table t2 (a varchar(10), filler char(200), key(a));
insert into t2 select * from t1;
explain select * from t1 where a between 'a' and 'a ';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 13 NULL # Using where
explain select * from t1 where a = 'a' or a='a ';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 13 NULL # Using where
explain select * from t2 where a between 'a' and 'a ';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref a a 13 const # Using where
explain select * from t2 where a = 'a' or a='a ';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ref a a 13 const # Using where
update t1 set a='b' where a<>'a';
explain select * from t1 where a not between 'b' and 'b';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 13 NULL # Using where
select a, hex(filler) from t1 where a not between 'b' and 'b';
a hex(filler)
a 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
drop table t1,t2,t3;
create table t1 (a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t2 (a int, key(a));
insert into t2 select 2*(A.a + 10*(B.a + 10*C.a)) from t1 A, t1 B, t1 C;
set @a="select * from t2 force index (a) where a NOT IN(0";
select count(*) from (select @a:=concat(@a, ',', a) from t2 ) Z;
count(*)
1000
set @a=concat(@a, ')');
insert into t2 values (11),(13),(15);
set @b= concat("explain ", @a);
prepare stmt1 from @b;
execute stmt1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index a a 5 NULL 1003 Using where; Using index
prepare stmt1 from @a;
execute stmt1;
a
11
13
15
drop table t1, t2;
CREATE TABLE t1 (
id int NOT NULL DEFAULT '0',
b int NOT NULL DEFAULT '0',
c int NOT NULL DEFAULT '0',
INDEX idx1(b,c), INDEX idx2(c));
INSERT INTO t1(id) VALUES (1), (2), (3), (4), (5), (6), (7), (8);
INSERT INTO t1(b,c) VALUES (3,4), (3,4);
SELECT * FROM t1 WHERE b<=3 AND 3<=c;
id b c
0 3 4
0 3 4
SELECT * FROM t1 WHERE 3 BETWEEN b AND c;
id b c
0 3 4
0 3 4
EXPLAIN SELECT * FROM t1 WHERE b<=3 AND 3<=c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range idx1,idx2 idx2 4 NULL 3 Using where
EXPLAIN SELECT * FROM t1 WHERE 3 BETWEEN b AND c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range idx1,idx2 idx2 4 NULL 3 Using where
SELECT * FROM t1 WHERE 0 < b OR 0 > c;
id b c
0 3 4
0 3 4
SELECT * FROM t1 WHERE 0 NOT BETWEEN b AND c;
id b c
0 3 4
0 3 4
EXPLAIN SELECT * FROM t1 WHERE 0 < b OR 0 > c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge idx1,idx2 idx1,idx2 4,4 NULL 4 Using sort_union(idx1,idx2); Using where
EXPLAIN SELECT * FROM t1 WHERE 0 NOT BETWEEN b AND c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index_merge idx1,idx2 idx1,idx2 4,4 NULL 4 Using sort_union(idx1,idx2); Using where
DROP TABLE t1;
CREATE TABLE t1 (
item char(20) NOT NULL default '',
started datetime NOT NULL default '0000-00-00 00:00:00',
price decimal(16,3) NOT NULL default '0.000',
PRIMARY KEY (item,started)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES
('A1','2005-11-01 08:00:00',1000),
('A1','2005-11-15 00:00:00',2000),
('A1','2005-12-12 08:00:00',3000),
('A2','2005-12-01 08:00:00',1000);
EXPLAIN SELECT * FROM t1 WHERE item='A1' AND started<='2005-12-01 24:00:00';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref PRIMARY PRIMARY 20 const 2 Using where
Warnings:
Warning 1292 Incorrect datetime value: '2005-12-01 24:00:00' for column 'started' at row 1
Warning 1292 Incorrect datetime value: '2005-12-01 24:00:00' for column 'started' at row 1
SELECT * FROM t1 WHERE item='A1' AND started<='2005-12-01 24:00:00';
item started price
A1 2005-11-01 08:00:00 1000.000
A1 2005-11-15 00:00:00 2000.000
Warnings:
Warning 1292 Incorrect datetime value: '2005-12-01 24:00:00' for column 'started' at row 1
Warning 1292 Incorrect datetime value: '2005-12-01 24:00:00' for column 'started' at row 1
SELECT * FROM t1 WHERE item='A1' AND started<='2005-12-02 00:00:00';
item started price
A1 2005-11-01 08:00:00 1000.000
A1 2005-11-15 00:00:00 2000.000
DROP INDEX `PRIMARY` ON t1;
EXPLAIN SELECT * FROM t1 WHERE item='A1' AND started<='2005-12-01 24:00:00';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
Warnings:
Warning 1292 Incorrect datetime value: '2005-12-01 24:00:00' for column 'started' at row 1
SELECT * FROM t1 WHERE item='A1' AND started<='2005-12-01 24:00:00';
item started price
A1 2005-11-01 08:00:00 1000.000
A1 2005-11-15 00:00:00 2000.000
Warnings:
Warning 1292 Incorrect datetime value: '2005-12-01 24:00:00' for column 'started' at row 1
SELECT * FROM t1 WHERE item='A1' AND started<='2005-12-02 00:00:00';
item started price
A1 2005-11-01 08:00:00 1000.000
A1 2005-11-15 00:00:00 2000.000
DROP TABLE t1;
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