MySQL的时间戳问题

Question

我在看一些练习题，

Assume that you've just created this table: 


CREATE TABLE timestamptest (
ts1 TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, 
i INT 
); 


When you look at its structure, you will notice that the TIMESTAMP column is declared NOT NULL. What happens if you insert these records: 

mysql> INSERT INTO timestamptest SET ts1=NULL, i=10; 
mysql> INSERT INTO timestamptest SET ts1=0, i=11; 
mysql> INSERT INTO timestamptest SET ts1='', i=12; 

俺们是

Only the first statement succeeds, and the TIMESTAMP column is set to the current date and time. The other two statements give an error: 

mysql> INSERT INTO timestamptest SET ts1=NULL, i=10; 
Query OK, 1 row affected (0.00 sec) 

mysql> INSERT INTO timestamptest SET ts1=0, i=11; 
ERROR 1292 (22007): Incorrect datetime value: '0' for column 'ts1' at row 1 
mysql> INSERT INTO timestamptest SET ts1='', i=12; 
ERROR 1292 (22007): Incorrect datetime value: '' for column 'ts1' at row 1 

但是当我试图，将TS1 = 0的作品，它插入一个零值时间戳...答案错了吗？

Answer 1

这取决于NO_ZERO_DATE选项是否设置：

mysql> create table foo(x timestamp); 
Query OK, 0 rows affected (0.01 sec) 

mysql> set sql_mode=''; 
Query OK, 0 rows affected (0.00 sec) 

mysql> insert into foo values(0); 
Query OK, 1 row affected (0.00 sec) 

mysql> set sql_mode='strict_all_tables,no_zero_date'; 
Query OK, 0 rows affected (0.00 sec) 

mysql> insert into foo values(0); 
ERROR 1292 (22007): Incorrect datetime value: '0' for column 'x' at row 1