经常用到的mysql函数

经常用到的mysql函数：

ABS() 

CEILING() (see CEILING() and FLOOR(), immediately following this list) 

DAY() 

DAYOFMONTH() 

DAYOFWEEK() 

DAYOFYEAR() 

DATEDIFF() 

EXTRACT() 

FLOOR() (see CEILING() and FLOOR(), immediately following this list) 

HOUR() 

MICROSECOND() 

MINUTE() 

MOD() 

MONTH() 

QUARTER() 

SECOND() 

TIME_TO_SEC() 

TO_DAYS() 

WEEKDAY() 

YEAR() 

YEARWEEK() 

例子：

时间戳转换：

SELECT FROM_UNIXTIME(1285722768114/1000) tdatetime, UNIX_TIMESTAMP(FROM_UNIXTIME(1285722768114/1000)) ttimestamp;

SELECT  DATE(FROM_UNIXTIME(1285722768114/1000))

 

SELECT  TIMESTAMP(FROM_UNIXTIME(1285722768114/1000))

SELECT FROM_UNIXTIME(1285722768114/1000) tdatetime, UNIX_TIMESTAMP("2010-09-29 09:12:48")*1000 ttimestamp;

 

拼接字符串：

UPDATE tbl_user SET email=CONCAT(SUBSTRING_INDEX(email,'@',1),'@newmail.com')