drop table if exists t1,t2; create table t1 (a int auto_increment , primary key (a)); insert into t1 values (NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL),(NULL); update t1 set a=a+10 where a > 34; update t1 set a=a+100 where a > 0; update t1 set a=a+100 where a=1 and a=2; update t1 set a=b+100 where a=1 and a=2; ERROR 42S22: Unknown column 'b' in 'field list' update t1 set a=b+100 where c=1 and a=2; ERROR 42S22: Unknown column 'c' in 'where clause' update t1 set d=a+100 where a=1; ERROR 42S22: Unknown column 'd' in 'field list' select * from t1; a 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 145 146 drop table t1; CREATE TABLE t1 ( place_id int (10) unsigned NOT NULL, shows int(10) unsigned DEFAULT '0' NOT NULL, ishows int(10) unsigned DEFAULT '0' NOT NULL, ushows int(10) unsigned DEFAULT '0' NOT NULL, clicks int(10) unsigned DEFAULT '0' NOT NULL, iclicks int(10) unsigned DEFAULT '0' NOT NULL, uclicks int(10) unsigned DEFAULT '0' NOT NULL, ts timestamp, PRIMARY KEY (place_id,ts) ); INSERT INTO t1 (place_id,shows,ishows,ushows,clicks,iclicks,uclicks,ts) VALUES (1,0,0,0,0,0,0,20000928174434); UPDATE t1 SET shows=shows+1,ishows=ishows+1,ushows=ushows+1,clicks=clicks+1,iclicks=iclicks+1,uclicks=uclicks+1 WHERE place_id=1 AND ts>="2000-09-28 00:00:00"; select place_id,shows from t1; place_id shows 1 1 drop table t1; CREATE TABLE t1 ( lfdnr int(10) unsigned NOT NULL default '0', ticket int(10) unsigned NOT NULL default '0', client varchar(255) NOT NULL default '', replyto varchar(255) NOT NULL default '', subject varchar(100) NOT NULL default '', timestamp int(10) unsigned NOT NULL default '0', tstamp timestamp NOT NULL, status int(3) NOT NULL default '0', type varchar(15) NOT NULL default '', assignment int(10) unsigned NOT NULL default '0', fupcount int(4) unsigned NOT NULL default '0', parent int(10) unsigned NOT NULL default '0', activity int(10) unsigned NOT NULL default '0', priority tinyint(1) unsigned NOT NULL default '1', cc varchar(255) NOT NULL default '', bcc varchar(255) NOT NULL default '', body text NOT NULL, comment text, header text, PRIMARY KEY (lfdnr), KEY k1 (timestamp), KEY k2 (type), KEY k3 (parent), KEY k4 (assignment), KEY ticket (ticket) ) ENGINE=MyISAM; INSERT INTO t1 VALUES (773,773,'','','',980257344,20010318180652,0,'Open',10,0,0,0,1,'','','','',''); alter table t1 change lfdnr lfdnr int(10) unsigned not null auto_increment; update t1 set status=1 where type='Open'; select status from t1; status 1 drop table t1; create table t1 (a int not null, b int not null, key (a)); insert into t1 values (1,1),(1,2),(1,3),(3,1),(3,2),(3,3),(3,1),(3,2),(3,3),(2,1),(2,2),(2,3); SET @tmp=0; update t1 set b=(@tmp:=@tmp+1) order by a; update t1 set b=99 where a=1 order by b asc limit 1; select * from t1 order by a,b; a b 1 2 1 3 1 99 2 4 2 5 2 6 3 7 3 8 3 9 3 10 3 11 3 12 update t1 set b=100 where a=1 order by b desc limit 2; update t1 set a=a+10+b where a=1 order by b; select * from t1 order by a,b; a b 2 4 2 5 2 6 3 7 3 8 3 9 3 10 3 11 3 12 13 2 111 100 111 100 create table t2 (a int not null, b int not null); insert into t2 values (1,1),(1,2),(1,3); update t1 set b=(select distinct 1 from (select * from t2) a); drop table t1,t2; CREATE TABLE t1 ( `id_param` smallint(3) unsigned NOT NULL default '0', `nom_option` char(40) NOT NULL default '', `valid` tinyint(1) NOT NULL default '0', KEY `id_param` (`id_param`,`nom_option`) ) ENGINE=MyISAM; INSERT INTO t1 (id_param,nom_option,valid) VALUES (185,'600x1200',1); UPDATE t1 SET nom_option='test' WHERE id_param=185 AND nom_option='600x1200' AND valid=1 LIMIT 1; select * from t1; id_param nom_option valid 185 test 1 drop table t1; create table t1 (F1 VARCHAR(30), F2 VARCHAR(30), F3 VARCHAR(30), cnt int, groupid int, KEY groupid_index (groupid)); insert into t1 (F1,F2,F3,cnt,groupid) values ('0','0','0',1,6), ('0','1','2',1,5), ('0','2','0',1,3), ('1','0','1',1,2), ('1','2','1',1,1), ('1','2','2',1,1), ('2','0','1',2,4), ('2','2','0',1,7); delete from m1 using t1 m1,t1 m2 where m1.groupid=m2.groupid and (m1.cnt < m2.cnt or m1.cnt=m2.cnt and m1.F3>m2.F3); select * from t1; F1 F2 F3 cnt groupid 0 0 0 1 6 0 1 2 1 5 0 2 0 1 3 1 0 1 1 2 1 2 1 1 1 2 0 1 2 4 2 2 0 1 7 drop table t1; CREATE TABLE t1 ( `colA` int(10) unsigned NOT NULL auto_increment, `colB` int(11) NOT NULL default '0', PRIMARY KEY (`colA`) ); INSERT INTO t1 VALUES (4433,5424); CREATE TABLE t2 ( `colC` int(10) unsigned NOT NULL default '0', `colA` int(10) unsigned NOT NULL default '0', `colD` int(10) unsigned NOT NULL default '0', `colE` int(10) unsigned NOT NULL default '0', `colF` int(10) unsigned NOT NULL default '0', PRIMARY KEY (`colC`,`colA`,`colD`,`colE`) ); INSERT INTO t2 VALUES (3,4433,10005,495,500); INSERT INTO t2 VALUES (3,4433,10005,496,500); INSERT INTO t2 VALUES (3,4433,10009,494,500); INSERT INTO t2 VALUES (3,4433,10011,494,500); INSERT INTO t2 VALUES (3,4433,10005,497,500); INSERT INTO t2 VALUES (3,4433,10013,489,500); INSERT INTO t2 VALUES (3,4433,10005,494,500); INSERT INTO t2 VALUES (3,4433,10005,493,500); INSERT INTO t2 VALUES (3,4433,10005,492,500); UPDATE IGNORE t2,t1 set t2.colE = t2.colE + 1,colF=0 WHERE t1.colA = t2.colA AND (t1.colB & 4096) > 0 AND (colE + 1) < colF; SELECT * FROM t2; colC colA colD colE colF 3 4433 10005 495 500 3 4433 10005 496 500 3 4433 10009 495 0 3 4433 10011 495 0 3 4433 10005 498 0 3 4433 10013 490 0 3 4433 10005 494 500 3 4433 10005 493 500 3 4433 10005 492 500 DROP TABLE t1; DROP TABLE t2; create table t1 (c1 int, c2 char(6), c3 int); create table t2 (c1 int, c2 char(6)); insert into t1 values (1, "t1c2-1", 10), (2, "t1c2-2", 20); update t1 left join t2 on t1.c1 = t2.c1 set t2.c2 = "t2c2-1"; update t1 left join t2 on t1.c1 = t2.c1 set t2.c2 = "t2c2-1" where t1.c3 = 10; drop table t1, t2; create table t1 (id int not null auto_increment primary key, id_str varchar(32)); insert into t1 (id_str) values ("test"); update t1 set id_str = concat(id_str, id) where id = last_insert_id(); select * from t1; id id_str 1 test1 drop table t1; create table t1 (a int, b char(255), key(a, b(20))); insert into t1 values (0, '1'); update t1 set b = b + 1 where a = 0; select * from t1; a b 0 2 drop table t1; create table t1 (a int, b varchar(10), key b(b(5))) engine=myisam; create table t2 (a int, b varchar(10)) engine=myisam; insert into t1 values ( 1, 'abcd1e'); insert into t1 values ( 2, 'abcd2e'); insert into t2 values ( 1, 'abcd1e'); insert into t2 values ( 2, 'abcd2e'); analyze table t1,t2; Table Op Msg_type Msg_text test.t1 analyze status OK test.t2 analyze status OK update t1, t2 set t1.a = t2.a where t2.b = t1.b; show warnings; Level Code Message drop table t1, t2; create table t1(f1 int, f2 int); create table t2(f3 int, f4 int); create index idx on t2(f3); insert into t1 values(1,0),(2,0); insert into t2 values(1,1),(2,2); UPDATE t1 SET t1.f2=(SELECT MAX(t2.f4) FROM t2 WHERE t2.f3=t1.f1); select * from t1; f1 f2 1 1 2 2 drop table t1,t2; create table t1(f1 int); select DATABASE(); DATABASE() test update t1 set f1=1 where count(*)=1; ERROR HY000: Invalid use of group function select DATABASE(); DATABASE() test delete from t1 where count(*)=1; ERROR HY000: Invalid use of group function drop table t1; create table t1 ( a int, b int default 0, index (a) ); insert into t1 (a) values (0),(0),(0),(0),(0),(0),(0),(0); flush status; select a from t1 order by a limit 1; a 0 show status like 'handler_read%'; Variable_name Value Handler_read_first 0 Handler_read_key 0 Handler_read_next 0 Handler_read_prev 0 Handler_read_rnd 0 Handler_read_rnd_next 0 flush status; update t1 set a=9999 order by a limit 1; analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status OK update t1 set b=9999 order by a desc limit 1; show status like 'handler_read%'; Variable_name Value Handler_read_first 0 Handler_read_key 0 Handler_read_next 0 Handler_read_prev 0 Handler_read_rnd 0 Handler_read_rnd_next 0 flush status; delete from t1 order by a limit 1; show status like 'handler_read%'; Variable_name Value Handler_read_first 0 Handler_read_key 0 Handler_read_next 0 Handler_read_prev 0 Handler_read_rnd 0 Handler_read_rnd_next 0 flush status; delete from t1 order by a desc limit 1; show status like 'handler_read%'; Variable_name Value Handler_read_first 0 Handler_read_key 0 Handler_read_next 0 Handler_read_prev 0 Handler_read_rnd 0 Handler_read_rnd_next 0 alter table t1 disable keys; Warnings: Note 1031 Table storage engine for 't1' doesn't have this option flush status; delete from t1 order by a limit 1; show status like 'handler_read%'; Variable_name Value Handler_read_first 0 Handler_read_key 0 Handler_read_next 0 Handler_read_prev 0 Handler_read_rnd 0 Handler_read_rnd_next 0 select * from t1; a b 0 0 0 0 0 0 0 0 0 0 update t1 set a=a+10,b=1 order by a limit 3; update t1 set a=a+11,b=2 order by a limit 3; update t1 set a=a+12,b=3 order by a limit 3; select * from t1 order by a; a b 11 2 21 2 22 3 22 3 23 3 drop table t1; create table t1 (f1 date not null); insert into t1 values('2000-01-01'),('0000-00-00'); update t1 set f1='2002-02-02' where f1 is null; select * from t1; f1 2000-01-01 2002-02-02 drop table t1; create table t1 (f1 int); create table t2 (f2 int); insert into t1 values(1),(2); insert into t2 values(1),(1); update t1,t2 set f1=3,f2=3 where f1=f2 and f1=1; affected rows: 3 info: Rows matched: 3 Changed: 3 Warnings: 0 update t2 set f2=1; update t1 set f1=1 where f1=3; update t2,t1 set f1=3,f2=3 where f1=f2 and f1=1; affected rows: 3 info: Rows matched: 3 Changed: 3 Warnings: 0 drop table t1,t2; create table t1 (a int); insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t2 (a int, filler1 char(200), filler2 char(200), key(a)); insert into t2 select A.a + 10*B.a, 'filler','filler' from t1 A, t1 B; flush status; update t2 set a=3 where a=2; show status like 'handler_read%'; Variable_name Value Handler_read_first 0 Handler_read_key 0 Handler_read_next 0 Handler_read_prev 0 Handler_read_rnd 0 Handler_read_rnd_next 0 drop table t1, t2; create table t1(f1 int, `*f2` int); insert into t1 values (1,1); update t1 set `*f2`=1; drop table t1;