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drop table if exists t1;
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;
Unknown column 'b' in 'field list'
update t1 set a=b+100 where c=1 and a=2;
Unknown column 'c' in 'where clause'
update t1 set d=a+100 where a=1;
Unknown column 'd' in 'field list'
select * from t1;
a
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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(14),
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(14) 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)
) TYPE=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 default 0 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);
insert into t1 values (1,1),(1,2),(1,3);
update t1 set b=4 where a=1 order by b asc limit 1;
update t1 set b=4 where a=1 order by b desc limit 1;
create table t2 (a int not null, b int not null);
insert into t2 values (1,1),(1,2),(1,3);
select * from t1;
a b
1 4
1 2
1 4
update t1 set b=(select distinct 1 from (select * from t2) a);
drop table t1,t2;
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