160
160
SELECT DISTINCT UserId FROM t1 WHERE UserId=22;
163
CREATE TABLE t1 (a int not null primary key,b int);
163
CREATE TABLE t1 (a int(10) unsigned not null primary key,b int(10) unsigned);
164
164
INSERT INTO t1 VALUES (1,1),(2,1),(3,1),(4,1);
165
CREATE TABLE t2 (a int not null, key (A));
165
CREATE TABLE t2 (a int(10) unsigned not null, key (A));
166
166
INSERT INTO t2 VALUES (1),(2);
167
CREATE TABLE t3 (a int, key(A), b text);
167
CREATE TABLE t3 (a int(10) unsigned, key(A), b text);
168
168
INSERT INTO t3 VALUES (1,'1'),(2,'2');
169
169
SELECT DISTINCT t3.b FROM t3,t2,t1 WHERE t3.a=t1.b AND t1.a=t2.a;
212
212
1 SIMPLE t1 index NULL PRIMARY 4 NULL 1 Using index
213
213
explain SELECT distinct a from t3 order by a desc limit 2;
214
214
id select_type table type possible_keys key key_len ref rows Extra
215
1 SIMPLE t3 index NULL a 5 NULL 2 Using index
215
1 SIMPLE t3 index NULL a 5 NULL 40 Using index
216
216
explain SELECT distinct a,b from t3 order by a+1;
217
217
id select_type table type possible_keys key key_len ref rows Extra
218
218
1 SIMPLE t3 ALL NULL NULL NULL NULL 204 Using temporary; Using filesort
219
219
explain SELECT distinct a,b from t3 order by a limit 2;
220
220
id select_type table type possible_keys key key_len ref rows Extra
221
1 SIMPLE t3 ALL NULL NULL NULL NULL 204 Using temporary; Using filesort
221
1 SIMPLE t3 index NULL a 5 NULL 2 Using temporary
222
222
explain SELECT a,b from t3 group by a,b order by a+1;
223
223
id select_type table type possible_keys key key_len ref rows Extra
224
224
1 SIMPLE t3 ALL NULL NULL NULL NULL 204 Using temporary; Using filesort
240
240
CREATE TABLE t1 (
241
ID int NOT NULL auto_increment,
241
ID int(11) NOT NULL auto_increment,
242
242
NAME varchar(75) DEFAULT '' NOT NULL,
243
LINK_ID int DEFAULT '0' NOT NULL,
243
LINK_ID int(11) DEFAULT '0' NOT NULL,
244
244
PRIMARY KEY (ID),
246
246
KEY LINK_ID (LINK_ID)
248
248
INSERT INTO t1 (ID, NAME, LINK_ID) VALUES (1,'Mike',0),(2,'Jack',0),(3,'Bill',0);
249
249
CREATE TABLE t2 (
250
ID int NOT NULL auto_increment,
250
ID int(11) NOT NULL auto_increment,
251
251
NAME varchar(150) DEFAULT '' NOT NULL,
252
252
PRIMARY KEY (ID),
402
402
test2@testdomain.com R002
403
403
test3@testdomain.com Z001
404
404
drop table t1,t2;
405
CREATE TABLE t1 (privatemessageid int NOT NULL auto_increment, folderid int NOT NULL default '0', userid int NOT NULL default '0', touserid int NOT NULL default '0', fromuserid int NOT NULL default '0', title varchar(250) NOT NULL default '', message mediumtext NOT NULL, dateline int NOT NULL default '0', showsignature int NOT NULL default '0', iconid int NOT NULL default '0', messageread int NOT NULL default '0', readtime int NOT NULL default '0', receipt int NOT NULL default '0', deleteprompt int NOT NULL default '0', multiplerecipients int NOT NULL default '0', PRIMARY KEY (privatemessageid), KEY userid (userid)) ENGINE=MyISAM;
405
CREATE TABLE t1 (privatemessageid int(10) unsigned NOT NULL auto_increment, folderid smallint(6) NOT NULL default '0', userid int(10) unsigned NOT NULL default '0', touserid int(10) unsigned NOT NULL default '0', fromuserid int(10) unsigned NOT NULL default '0', title varchar(250) NOT NULL default '', message mediumtext NOT NULL, dateline int(10) unsigned NOT NULL default '0', showsignature smallint(6) NOT NULL default '0', iconid smallint(5) unsigned NOT NULL default '0', messageread smallint(6) NOT NULL default '0', readtime int(10) unsigned NOT NULL default '0', receipt smallint(6) unsigned NOT NULL default '0', deleteprompt smallint(6) unsigned NOT NULL default '0', multiplerecipients smallint(6) unsigned NOT NULL default '0', PRIMARY KEY (privatemessageid), KEY userid (userid)) ENGINE=MyISAM;
406
406
INSERT INTO t1 VALUES (128,0,33,33,8,':D','',996121863,1,0,2,996122850,2,0,0);
407
CREATE TABLE t2 (userid int NOT NULL auto_increment, usergroupid int NOT NULL default '0', username varchar(50) NOT NULL default '', password varchar(50) NOT NULL default '', email varchar(50) NOT NULL default '', styleid int NOT NULL default '0', parentemail varchar(50) NOT NULL default '', coppauser int NOT NULL default '0', homepage varchar(100) NOT NULL default '', icq varchar(20) NOT NULL default '', aim varchar(20) NOT NULL default '', yahoo varchar(20) NOT NULL default '', signature mediumtext NOT NULL, adminemail int NOT NULL default '0', showemail int NOT NULL default '0', invisible int NOT NULL default '0', usertitle varchar(250) NOT NULL default '', customtitle int NOT NULL default '0', joindate int NOT NULL default '0', cookieuser int NOT NULL default '0', daysprune int NOT NULL default '0', lastvisit int NOT NULL default '0', lastactivity int NOT NULL default '0', lastpost int NOT NULL default '0', posts int NOT NULL default '0', timezoneoffset varchar(4) NOT NULL default '', emailnotification int NOT NULL default '0', buddylist mediumtext NOT NULL, ignorelist mediumtext NOT NULL, pmfolders mediumtext NOT NULL, receivepm int NOT NULL default '0', emailonpm int NOT NULL default '0', pmpopup int NOT NULL default '0', avatarid int NOT NULL default '0', avatarrevision int NOT NULL default '0', options int NOT NULL default '15', birthday date NOT NULL default '0000-00-00', maxposts int NOT NULL default '-1', startofweek int NOT NULL default '1', ipaddress varchar(20) NOT NULL default '', referrerid int NOT NULL default '0', nosessionhash int NOT NULL default '0', autorefresh int NOT NULL default '-1', messagepopup int NOT NULL default '0', inforum int NOT NULL default '0', ratenum int NOT NULL default '0', ratetotal int NOT NULL default '0', allowrate int NOT NULL default '1', PRIMARY KEY (userid), KEY usergroupid (usergroupid), KEY username (username), KEY inforum (inforum)) ENGINE=MyISAM;
407
CREATE TABLE t2 (userid int(10) unsigned NOT NULL auto_increment, usergroupid smallint(5) unsigned NOT NULL default '0', username varchar(50) NOT NULL default '', password varchar(50) NOT NULL default '', email varchar(50) NOT NULL default '', styleid smallint(5) unsigned NOT NULL default '0', parentemail varchar(50) NOT NULL default '', coppauser smallint(6) NOT NULL default '0', homepage varchar(100) NOT NULL default '', icq varchar(20) NOT NULL default '', aim varchar(20) NOT NULL default '', yahoo varchar(20) NOT NULL default '', signature mediumtext NOT NULL, adminemail smallint(6) NOT NULL default '0', showemail smallint(6) NOT NULL default '0', invisible smallint(6) NOT NULL default '0', usertitle varchar(250) NOT NULL default '', customtitle smallint(6) NOT NULL default '0', joindate int(10) unsigned NOT NULL default '0', cookieuser smallint(6) NOT NULL default '0', daysprune smallint(6) NOT NULL default '0', lastvisit int(10) unsigned NOT NULL default '0', lastactivity int(10) unsigned NOT NULL default '0', lastpost int(10) unsigned NOT NULL default '0', posts smallint(5) unsigned NOT NULL default '0', timezoneoffset varchar(4) NOT NULL default '', emailnotification smallint(6) NOT NULL default '0', buddylist mediumtext NOT NULL, ignorelist mediumtext NOT NULL, pmfolders mediumtext NOT NULL, receivepm smallint(6) NOT NULL default '0', emailonpm smallint(6) NOT NULL default '0', pmpopup smallint(6) NOT NULL default '0', avatarid smallint(6) NOT NULL default '0', avatarrevision int(6) unsigned NOT NULL default '0', options smallint(6) NOT NULL default '15', birthday date NOT NULL default '0000-00-00', maxposts smallint(6) NOT NULL default '-1', startofweek smallint(6) NOT NULL default '1', ipaddress varchar(20) NOT NULL default '', referrerid int(10) unsigned NOT NULL default '0', nosessionhash smallint(6) NOT NULL default '0', autorefresh smallint(6) NOT NULL default '-1', messagepopup tinyint(2) NOT NULL default '0', inforum smallint(5) unsigned NOT NULL default '0', ratenum smallint(5) unsigned NOT NULL default '0', ratetotal smallint(5) unsigned NOT NULL default '0', allowrate smallint(5) unsigned NOT NULL default '1', PRIMARY KEY (userid), KEY usergroupid (usergroupid), KEY username (username), KEY inforum (inforum)) ENGINE=MyISAM;
408
408
INSERT INTO t2 VALUES (33,6,'Kevin','0','kevin@stileproject.com',1,'',0,'http://www.stileproject.com','','','','',1,1,0,'Administrator',0,996120694,1,-1,1030996168,1031027028,1030599436,36,'-6',0,'','','',1,0,1,0,0,15,'0000-00-00',-1,1,'64.0.0.0',0,1,-1,0,0,4,19,1);
409
409
SELECT DISTINCT t1.*, t2.* FROM t1 LEFT JOIN t2 ON (t2.userid = t1.touserid);
410
410
privatemessageid folderid userid touserid fromuserid title message dateline showsignature iconid messageread readtime receipt deleteprompt multiplerecipients userid usergroupid username password email styleid parentemail coppauser homepage icq aim yahoo signature adminemail showemail invisible usertitle customtitle joindate cookieuser daysprune lastvisit lastactivity lastpost posts timezoneoffset emailnotification buddylist ignorelist pmfolders receivepm emailonpm pmpopup avatarid avatarrevision options birthday maxposts startofweek ipaddress referrerid nosessionhash autorefresh messagepopup inforum ratenum ratetotal allowrate
608
608
SELECT DISTINCT a,a FROM t1 WHERE b < 12 ORDER BY a;
611
CREATE TABLE t1 (a CHAR(1));
612
INSERT INTO t1 VALUES('A'), (0);
613
SELECT a FROM t1 WHERE a=0;
618
Warning 1292 Truncated incorrect DOUBLE value: 'A'
619
SELECT DISTINCT a FROM t1 WHERE a=0;
624
Warning 1292 Truncated incorrect DOUBLE value: 'A'
626
CREATE TABLE t1 (a DATE);
627
INSERT INTO t1 VALUES ('1972-07-29'), ('1972-02-06');
628
EXPLAIN SELECT (SELECT DISTINCT a FROM t1 WHERE a = '2002-08-03');
629
id select_type table type possible_keys key key_len ref rows Extra
630
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL No tables used
631
2 SUBQUERY t1 ALL NULL NULL NULL NULL 2 Using where
632
EXPLAIN SELECT (SELECT DISTINCT ADDDATE(a,1) FROM t1
633
WHERE ADDDATE(a,1) = '2002-08-03');
634
id select_type table type possible_keys key key_len ref rows Extra
635
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL No tables used
636
2 SUBQUERY t1 ALL NULL NULL NULL NULL 2 Using where
637
CREATE TABLE t2 (a CHAR(5) CHARACTER SET latin1 COLLATE latin1_general_ci);
638
INSERT INTO t2 VALUES (0xf6);
639
INSERT INTO t2 VALUES ('oe');
640
SELECT COUNT(*) FROM (SELECT DISTINCT a FROM t2) dt;
644
(SELECT DISTINCT a FROM t2 WHERE a='oe' COLLATE latin1_german2_ci) dt;
611
648
CREATE TABLE t1 (a INT, UNIQUE (a));
612
649
INSERT INTO t1 VALUES (4),(null),(2),(1),(null),(3);
613
650
EXPLAIN SELECT DISTINCT a FROM t1;