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drop table if exists t1,t2;
CREATE TABLE t1 (a int, t timestamp);
CREATE TABLE t2 (a int, t datetime);
SET TIMESTAMP=1234;
insert into t1 values(1,NULL);
insert into t1 values(2,"2002-03-03");
SET TIMESTAMP=1235;
insert into t1 values(3,NULL);
SET TIMESTAMP=1236;
insert into t1 (a) values(4);
insert into t2 values(5,"2002-03-04"),(6,NULL),(7,"2002-03-05"),(8,NULL);
SET TIMESTAMP=1237;
insert into t1 select * from t2;
SET TIMESTAMP=1238;
insert into t1 (a) select a+1 from t2 where a=8;
select * from t1;
a t
1 NULL
2 2002-03-03 00:00:00
3 NULL
4 NULL
5 2002-03-04 00:00:00
6 NULL
7 2002-03-05 00:00:00
8 NULL
9 NULL
drop table t1,t2;
SET TIMESTAMP=1234;
CREATE TABLE t1 (value TEXT NOT NULL, id VARCHAR(32) NOT NULL, stamp timestamp, PRIMARY KEY (id));
INSERT INTO t1 VALUES ("my value", "myKey","1999-04-02 00:00:00");
SELECT stamp FROM t1 WHERE id="myKey";
stamp
1999-04-02 00:00:00
UPDATE t1 SET value="my value" WHERE id="myKey";
SELECT stamp FROM t1 WHERE id="myKey";
stamp
1999-04-02 00:00:00
UPDATE t1 SET id="myKey" WHERE value="my value";
SELECT stamp FROM t1 WHERE id="myKey";
stamp
1999-04-02 00:00:00
drop table t1;
create table t1 (a timestamp);
insert into t1 values (now());
select date_format(a,"%Y %y"),year(a),year(now()) from t1;
date_format(a,"%Y %y") year(a) year(now())
1970 70 1970 1970
drop table t1;
create table t1 (ix timestamp);
insert into t1 values (19991101000000),(19990102030405),(19990630232922),(19990601000000),(19990930232922),(19990531232922),(19990501000000),(19991101000000),(19990501000000);
select ix+0 from t1;
ix+0
19991101000000
19990102030405
19990630232922
19990601000000
19990930232922
19990531232922
19990501000000
19991101000000
19990501000000
truncate table t1;
insert into t1 values ("19991101000000"),("19990102030405"),("19990630232922"),("19990601000000");
select ix+0 from t1;
ix+0
19991101000000
19990102030405
19990630232922
19990601000000
drop table t1;
CREATE TABLE t1 (date date, date_time datetime, time_stamp timestamp);
INSERT INTO t1 VALUES ("1998-12-31","1998-12-31 23:59:59",19981231235959);
INSERT INTO t1 VALUES ("1999-01-01","1999-01-01 00:00:00",19990101000000);
INSERT INTO t1 VALUES ("1999-09-09","1999-09-09 23:59:59",19990909235959);
INSERT INTO t1 VALUES ("2000-01-01","2000-01-01 00:00:00",20000101000000);
INSERT INTO t1 VALUES ("2000-02-28","2000-02-28 00:00:00",20000228000000);
INSERT INTO t1 VALUES ("2000-02-29","2000-02-29 00:00:00",20000229000000);
INSERT INTO t1 VALUES ("2000-03-01","2000-03-01 00:00:00",20000301000000);
INSERT INTO t1 VALUES ("2000-12-31","2000-12-31 23:59:59",20001231235959);
INSERT INTO t1 VALUES ("2001-01-01","2001-01-01 00:00:00",20010101000000);
INSERT INTO t1 VALUES ("2004-12-31","2004-12-31 23:59:59",20041231235959);
INSERT INTO t1 VALUES ("2005-01-01","2005-01-01 00:00:00",20050101000000);
INSERT INTO t1 VALUES ("2030-01-01","2030-01-01 00:00:00",20300101000000);
SELECT * FROM t1;
date date_time time_stamp
1998-12-31 1998-12-31 23:59:59 1998-12-31 23:59:59
1999-01-01 1999-01-01 00:00:00 1999-01-01 00:00:00
1999-09-09 1999-09-09 23:59:59 1999-09-09 23:59:59
2000-01-01 2000-01-01 00:00:00 2000-01-01 00:00:00
2000-02-28 2000-02-28 00:00:00 2000-02-28 00:00:00
2000-02-29 2000-02-29 00:00:00 2000-02-29 00:00:00
2000-03-01 2000-03-01 00:00:00 2000-03-01 00:00:00
2000-12-31 2000-12-31 23:59:59 2000-12-31 23:59:59
2001-01-01 2001-01-01 00:00:00 2001-01-01 00:00:00
2004-12-31 2004-12-31 23:59:59 2004-12-31 23:59:59
2005-01-01 2005-01-01 00:00:00 2005-01-01 00:00:00
2030-01-01 2030-01-01 00:00:00 2030-01-01 00:00:00
drop table t1;
create table t1 (t2 timestamp, t4 timestamp, t6 timestamp,
t8 timestamp, t10 timestamp, t12 timestamp,
t14 timestamp);
insert t1 values
("1997-12-31 23:47:59", "1997-12-31 23:47:59", "1997-12-31 23:47:59",
"1997-12-31 23:47:59", "1997-12-31 23:47:59", "1997-12-31 23:47:59",
"1997-12-31 23:47:59");
select * from t1;
t2 t4 t6 t8 t10 t12 t14
1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59
select * from t1;
t2 t4 t6 t8 t10 t12 t14
1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59 1997-12-31 23:47:59
drop table t1;
create table t1 (ix timestamp);
insert into t1 values (0),(20030101010160),(20030101016001),(20030101240101),(20030132010101),(20031301010101),(20031200000000),(20030000000000);
ERROR HY000: Received an invalid timestamp value '0'.
select ix+0 from t1;
ix+0
truncate table t1;
insert into t1 values ("00000000000000"),("20030101010160"),("20030101016001"),("20030101240101"),("20030132010101"),("20031301010101"),("20031200000000"),("20030000000000");
ERROR HY000: Received an invalid timestamp value '00000000000000'.
select ix+0 from t1;
ix+0
truncate table t1;
insert into t1 values ("0000-00-00 00:00:00 some trailer"),("2003-01-01 00:00:00 some trailer");
ERROR HY000: Received an invalid timestamp value '0000-00-00 00:00:00 some trailer'.
select ix+0 from t1;
ix+0
drop table t1;
create table t1 (t1 timestamp default now(), t2 timestamp on update now());
ERROR HY000: Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause
create table t1 (t1 timestamp on update now(), t2 timestamp default now() on update now());
ERROR HY000: Incorrect table definition; there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT or ON UPDATE clause
create table t1 (t1 timestamp default '2003-01-01 00:00:00', t2 datetime, t3 timestamp);
SET TIMESTAMP=1000000000;
insert into t1 values ();
SET TIMESTAMP=1000000001;
update t1 set t2=now();
SET TIMESTAMP=1000000002;
insert into t1 (t1,t3) values (default, default);
select * from t1;
t1 t2 t3
2003-01-01 00:00:00 2001-09-09 01:46:41 NULL
2003-01-01 00:00:00 NULL NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`t1` TIMESTAMP NULL DEFAULT '2003-01-01 00:00:00',
`t2` DATETIME DEFAULT NULL,
`t3` TIMESTAMP NULL DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
show columns from t1;
Field Type Null Default Default_is_NULL On_Update
t1 TIMESTAMP YES 2003-01-01 00:00:00 NO
t2 DATETIME YES YES
t3 TIMESTAMP YES YES
drop table t1;
create table t1 (t1 timestamp default now(), t2 datetime, t3 timestamp);
SET TIMESTAMP=1000000002;
insert into t1 values ();
SET TIMESTAMP=1000000003;
update t1 set t2=now();
SET TIMESTAMP=1000000003;
insert into t1 (t1,t3) values (default, default);
select * from t1;
t1 t2 t3
2001-09-09 01:46:42 2001-09-09 01:46:43 NULL
2001-09-09 01:46:43 NULL NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`t1` TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP,
`t2` DATETIME DEFAULT NULL,
`t3` TIMESTAMP NULL DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
show columns from t1;
Field Type Null Default Default_is_NULL On_Update
t1 TIMESTAMP YES CURRENT_TIMESTAMP YES
t2 DATETIME YES YES
t3 TIMESTAMP YES YES
drop table t1;
create table t1 (t1 timestamp default '2003-01-01 00:00:00' on update now(), t2 datetime);
SET TIMESTAMP=1000000004;
insert into t1 values ();
select * from t1;
t1 t2
2003-01-01 00:00:00 NULL
SET TIMESTAMP=1000000005;
update t1 set t2=now();
SET TIMESTAMP=1000000005;
insert into t1 (t1) values (default);
select * from t1;
t1 t2
2001-09-09 01:46:45 2001-09-09 01:46:45
2003-01-01 00:00:00 NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`t1` TIMESTAMP NULL DEFAULT '2003-01-01 00:00:00' ON UPDATE CURRENT_TIMESTAMP,
`t2` DATETIME DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
show columns from t1;
Field Type Null Default Default_is_NULL On_Update
t1 TIMESTAMP YES 2003-01-01 00:00:00 NO CURRENT_TIMESTAMP
t2 DATETIME YES YES
drop table t1;
create table t1 (t1 timestamp default now() on update now(), t2 datetime);
SET TIMESTAMP=1000000006;
insert into t1 values ();
select * from t1;
t1 t2
2001-09-09 01:46:46 NULL
SET TIMESTAMP=1000000007;
update t1 set t2=now();
SET TIMESTAMP=1000000007;
insert into t1 (t1) values (default);
select * from t1;
t1 t2
2001-09-09 01:46:47 2001-09-09 01:46:47
2001-09-09 01:46:47 NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`t1` TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`t2` DATETIME DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
show columns from t1;
Field Type Null Default Default_is_NULL On_Update
t1 TIMESTAMP YES CURRENT_TIMESTAMP YES CURRENT_TIMESTAMP
t2 DATETIME YES YES
drop table t1;
create table t1 (t1 timestamp, t2 datetime, t3 timestamp);
SET TIMESTAMP=1000000007;
insert into t1 values ();
select * from t1;
t1 t2 t3
NULL NULL NULL
SET TIMESTAMP=1000000008;
update t1 set t2=now();
SET TIMESTAMP=1000000008;
insert into t1 (t1,t3) values (default, default);
select * from t1;
t1 t2 t3
NULL 2001-09-09 01:46:48 NULL
NULL NULL NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`t1` TIMESTAMP NULL DEFAULT NULL,
`t2` DATETIME DEFAULT NULL,
`t3` TIMESTAMP NULL DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
show columns from t1;
Field Type Null Default Default_is_NULL On_Update
t1 TIMESTAMP YES YES
t2 DATETIME YES YES
t3 TIMESTAMP YES YES
drop table t1;
create table t1 (t1 timestamp default current_timestamp on update current_timestamp, t2 datetime);
SET TIMESTAMP=1000000009;
insert into t1 values ();
select * from t1;
t1 t2
2001-09-09 01:46:49 NULL
SET TIMESTAMP=1000000010;
update t1 set t2=now();
SET TIMESTAMP=1000000011;
insert into t1 (t1) values (default);
select * from t1;
t1 t2
2001-09-09 01:46:50 2001-09-09 01:46:50
2001-09-09 01:46:51 NULL
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`t1` TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`t2` DATETIME DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
show columns from t1;
Field Type Null Default Default_is_NULL On_Update
t1 TIMESTAMP YES CURRENT_TIMESTAMP YES CURRENT_TIMESTAMP
t2 DATETIME YES YES
truncate table t1;
insert into t1 values ('2004-04-01 00:00:00', '2004-04-01 00:00:00');
SET TIMESTAMP=1000000012;
update t1 set t1= '2004-04-02 00:00:00';
select * from t1;
t1 t2
2004-04-02 00:00:00 2004-04-01 00:00:00
update t1 set t1.t1= '2004-04-03 00:00:00';
select * from t1;
t1 t2
2004-04-03 00:00:00 2004-04-01 00:00:00
drop table t1;
create table t1 (pk int primary key, t1 timestamp default current_timestamp on update current_timestamp, bulk int);
insert into t1 values (1, '2004-04-01 00:00:00', 10);
SET TIMESTAMP=1000000013;
replace into t1 set pk = 1, bulk= 20;
select * from t1;
pk t1 bulk
1 2001-09-09 01:46:53 20
drop table t1;
create table t1 (pk int primary key, t1 timestamp default '2003-01-01 00:00:00' on update current_timestamp, bulk int);
insert into t1 values (1, '2004-04-01 00:00:00', 10);
SET TIMESTAMP=1000000014;
replace into t1 set pk = 1, bulk= 20;
select * from t1;
pk t1 bulk
1 2003-01-01 00:00:00 20
drop table t1;
create table t1 (pk int primary key, t1 timestamp default current_timestamp, bulk int);
insert into t1 values (1, '2004-04-01 00:00:00', 10);
SET TIMESTAMP=1000000015;
replace into t1 set pk = 1, bulk= 20;
select * from t1;
pk t1 bulk
1 2001-09-09 01:46:55 20
drop table t1;
create table t1 (t1 timestamp default current_timestamp on update current_timestamp);
insert into t1 values ('2004-04-01 00:00:00');
SET TIMESTAMP=1000000016;
alter table t1 add i int default 10;
select * from t1;
t1 i
2004-04-01 00:00:00 10
drop table t1;
create table t1 (a timestamp null, b timestamp null);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` TIMESTAMP NULL DEFAULT NULL,
`b` TIMESTAMP NULL DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
insert into t1 values (NULL, NULL);
SET TIMESTAMP=1000000017;
insert into t1 values ();
select * from t1;
a b
NULL NULL
NULL NULL
drop table t1;
create table t1 (a timestamp null default current_timestamp on update current_timestamp, b timestamp null);
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`b` TIMESTAMP NULL DEFAULT NULL
) ENGINE=DEFAULT COLLATE = utf8_general_ci
insert into t1 values (NULL, NULL);
SET TIMESTAMP=1000000018;
insert into t1 values ();
select * from t1;
a b
NULL NULL
2001-09-09 01:46:58 NULL
drop table t1;
create table t1 (a timestamp null default null, b timestamp null default '2003-01-01 00:00:00');
show create table t1;
Table Create Table
t1 CREATE TABLE `t1` (
`a` TIMESTAMP NULL DEFAULT NULL,
`b` TIMESTAMP NULL DEFAULT '2003-01-01 00:00:00'
) ENGINE=DEFAULT COLLATE = utf8_general_ci
insert into t1 values (NULL, NULL);
insert into t1 values (DEFAULT, DEFAULT);
select * from t1;
a b
NULL NULL
NULL 2003-01-01 00:00:00
drop table t1;
create table t1 (a bigint, b bigint);
insert into t1 values (NULL, NULL), (20030101000000, 20030102000000);
set timestamp=1000000019;
alter table t1 modify a timestamp, modify b timestamp;
select * from t1;
a b
NULL NULL
2003-01-01 00:00:00 2003-01-02 00:00:00
drop table t1;
create table t1 (a char(2), t timestamp);
insert into t1 values ('a', '2004-01-01 00:00:00'), ('a', '2004-01-01 01:00:00'),
('b', '2004-02-01 00:00:00');
select max(t) from t1 group by a;
max(t)
2004-01-01 01:00:00
2004-02-01 00:00:00
drop table t1;
create table t1 (a int auto_increment primary key, b int, c timestamp);
insert into t1 (a, b, c) values (1, 0, '2001-01-01 01:01:01'),
(2, 0, '2002-02-02 02:02:02'), (3, 0, '2003-03-03 03:03:03');
select * from t1;
a b c
1 0 2001-01-01 01:01:01
2 0 2002-02-02 02:02:02
3 0 2003-03-03 03:03:03
update t1 set b = 2, c = c where a = 2;
select * from t1;
a b c
1 0 2001-01-01 01:01:01
2 2 2002-02-02 02:02:02
3 0 2003-03-03 03:03:03
insert into t1 (a) values (4);
select * from t1;
a b c
1 0 2001-01-01 01:01:01
2 2 2002-02-02 02:02:02
3 0 2003-03-03 03:03:03
4 NULL NULL
update t1 set c = '2004-04-04 04:04:04' where a = 4;
select * from t1;
a b c
1 0 2001-01-01 01:01:01
2 2 2002-02-02 02:02:02
3 0 2003-03-03 03:03:03
4 NULL 2004-04-04 04:04:04
insert into t1 (a) values (3), (5) on duplicate key update b = 3, c = c;
select * from t1;
a b c
1 0 2001-01-01 01:01:01
2 2 2002-02-02 02:02:02
3 3 2003-03-03 03:03:03
4 NULL 2004-04-04 04:04:04
5 NULL NULL
insert into t1 (a, c) values (4, '2004-04-04 00:00:00'),
(6, '2006-06-06 06:06:06') on duplicate key update b = 4;
select * from t1;
a b c
1 0 2001-01-01 01:01:01
2 2 2002-02-02 02:02:02
3 3 2003-03-03 03:03:03
4 4 2004-04-04 04:04:04
5 NULL NULL
6 NULL 2006-06-06 06:06:06
drop table t1;
CREATE TABLE t1 (
`id` int NOT NULL auto_increment,
`username` varchar(80) NOT NULL default '',
`posted_on` timestamp NOT NULL default now(),
PRIMARY KEY (`id`)
) AUTO_INCREMENT=1;
show fields from t1;
Field Type Null Default Default_is_NULL On_Update
id INTEGER NO NO
username VARCHAR NO NO
posted_on TIMESTAMP NO CURRENT_TIMESTAMP NO
select is_nullable from data_dictionary.columns where TABLE_NAME='t1' and COLUMN_NAME='posted_on';
is_nullable
NO
drop table t1;
|