MySQL会根据当前时区转化TIMESTAMP值，在查询时候会根据当前时区来处理。

mysql> create table test2(a int(20));
Query OK, 0 rows affected (0.07 sec)

mysql> insert into test2 values(1466929145);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test2;
+------------+
| a |
+------------+
| 1466929145 |
+------------+
1 row in set (0.00 sec)

mysql> select from_unixtime(a) from test2;
+---------------------+
| from_unixtime(a) |
+---------------------+
| 2016-06-26 08:19:05 |
+---------------------+
1 row in set (0.00 sec)

mysql> insert into test2 values(14669291450);
Query OK, 1 row affected, 1 warning (0.00 sec)

mysql> select from_unixtime(a) from test2;
+---------------------+
| from_unixtime(a) |
+---------------------+
| 2016-06-26 08:19:05 |
| 2038-01-19 03:14:07 |
+---------------------+
2 rows in set (0.00 sec)

mysql> insert into test2 values(14669291450);
Query OK, 1 row affected, 1 warning (0.00 sec)

mysql> show warnings;
+---------+------+--------------------------------------------+
| Level | Code | Message |
+---------+------+--------------------------------------------+
| Warning | 1264 | Out of range value for column 'a' at row 1 |
+---------+------+--------------------------------------------+
1 row in set (0.00 sec)

mysql> select from_unixtime(a) from test2;
+---------------------+
| from_unixtime(a) |
+---------------------+
| 2016-06-26 08:19:05 |
| 2038-01-19 03:14:07 |
| 2038-01-19 03:14:07 |
+---------------------+
3 rows in set (0.00 sec)

查看当前时区
mysql> show variables like 'time_zone';
+---------------+--------+
| Variable_name | Value |
+---------------+--------+
| time_zone | +00:00 |
+---------------+--------+
1 row in set (0.00 sec)

更改会话时区参数后，可以看到查询出来的时间发生了变化
mysql> set session time_zone='+01:00';
Query OK, 0 rows affected (0.00 sec)

mysql> select from_unixtime(a) from test2;
+---------------------+
| from_unixtime(a) |
+---------------------+
| 2016-06-26 09:19:05 |
| 2038-01-19 04:14:07 |
| 2038-01-19 04:14:07 |
+---------------------+
3 rows in set (0.00 sec)

datetime不受时区的影响
mysql> create table test3(a datetime);
Query OK, 0 rows affected (0.10 sec)

mysql> select * from test3;
Empty set (0.00 sec)

mysql> insert into test3 values(now());
Query OK, 1 row affected (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.02 sec)

mysql> select * from test3;
+---------------------+
| a |
+---------------------+
| 2017-02-13 10:02:20 |
+---------------------+
1 row in set (0.00 sec)

mysql> set session time_zone='+10:00';
Query OK, 0 rows affected (0.00 sec)

mysql> show variables like 'time_zone';
+---------------+--------+
| Variable_name | Value |
+---------------+--------+
| time_zone | +10:00 |
+---------------+--------+
1 row in set (0.00 sec)

mysql> select * from test3;
+---------------------+
| a |
+---------------------+
| 2017-02-13 10:02:20 |
+---------------------+
1 row in set (0.00 sec)