MySQL中datetime和timestamp的区别及使用详解

mysql> create table test(id int,hiredate date);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into test values(1,'20151208000000');
Query OK, 1 row affected (0.00 sec)

mysql> insert into test values(1,'20151208104400');
Query OK, 1 row affected, 1 warning (0.01 sec)

mysql> show warning;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'warning' at line 1
mysql> select * from test;
+------+------------+
| id  | hiredate  |
+------+------------+
|  1 | 2015-12-08 |
|  1 | 2015-12-08 |
+------+------------+
2 rows in set (0.00 sec)

mysql> create table test(id int,hiredate timestamp);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into test values(1,'20151208000000');
Query OK, 1 row affected (0.00 sec)

mysql> create table test1(id int,hiredate datetime);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into test1 values(1,'20151208000000');
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+---------------------+
| id  | hiredate      |
+------+---------------------+
|  1 | 2015-12-08 00:00:00 |
+------+---------------------+
1 row in set (0.01 sec)

mysql> select * from test1;
+------+---------------------+
| id  | hiredate      |
+------+---------------------+
|  1 | 2015-12-08 00:00:00 |
+------+---------------------+
1 row in set (0.00 sec)

mysql> show variables like '%time_zone%'; 
+------------------+--------+
| Variable_name  | Value |
+------------------+--------+
| system_time_zone | CST  |
| time_zone    | SYSTEM |
+------------------+--------+
2 rows in set (0.00 sec)

mysql> set time_zone='+0:00';
Query OK, 0 rows affected (0.00 sec)

mysql> select * from test;
+------+---------------------+
| id  | hiredate      |
+------+---------------------+
|  1 | 2015-12-07 16:00:00 |
+------+---------------------+
1 row in set (0.00 sec)

mysql> select * from test1;
+------+---------------------+
| id  | hiredate      |
+------+---------------------+
|  1 | 2015-12-08 00:00:00 |
+------+---------------------+
1 row in set (0.01 sec)

mysql> create table test(id int,hiredate timestamp);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into test(id) values(1);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+---------------------+
| id  | hiredate      |
+------+---------------------+
|  1 | 2015-12-08 14:34:46 |
+------+---------------------+
1 row in set (0.00 sec)

mysql> show create table test\G
*************************** 1. row ***************************
    Table: test
Create Table: CREATE TABLE `test` (
 `id` int(11) DEFAULT NULL,
 `hiredate` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)

mysql> show variables like '%explicit_defaults_for_timestamp%';
+---------------------------------+-------+
| Variable_name          | Value |
+---------------------------------+-------+
| explicit_defaults_for_timestamp | OFF  |
+---------------------------------+-------+
1 row in set (0.00 sec)

mysql> create table test1(id int,hiredate timestamp null);
Query OK, 0 rows affected (0.01 sec)

mysql> show create table test1\G
*************************** 1. row ***************************
    Table: test1
Create Table: CREATE TABLE `test1` (
 `id` int(11) DEFAULT NULL,
 `hiredate` timestamp NULL DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)

mysql> create table test2(id int,hiredate timestamp default 0);
Query OK, 0 rows affected (0.01 sec)

mysql> show create table test2\G
*************************** 1. row ***************************
    Table: test2
Create Table: CREATE TABLE `test2` (
 `id` int(11) DEFAULT NULL,
 `hiredate` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00'
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)