mysql常用字符串函数

yyyy-MM-dd
select left('2013-12-13 14:15:16',10)

hh:mm:ss
select right('2013-12-13 14:15:16',8)

MM
select substring('2013-12-13 14:15:16',6,2)

ss
select substring('2013-12-13 14:15:16',-2)

mm
select substring('2013-12-13 14:15:16',-5,2)

www.iteye
select substring_index('www.iteye.com','.',2)

www
select substring_index('www.iteye.com','.',1)

com
select substring_index('www.iteye.com','.',-1)

www.iteye.com
select substring_index('www.iteye.com','.cn',-1)

select ltrim(' abc ')
select rtrim(' abc ')
select trim(' abc ')

select trim(leading 'x' from 'xxxbarxxx');
select trim(trailing 'x' from 'xxxbarxxx');
select trim(both 'x' from 'xxxbarxxx');

select replace('2012-12-12','12',11)
--替换image.cache为image
update db_sols set url = replace(url,"image.cache","image")
select insert('2012-12-12',9,2,'11')

select reverse('2012-12-12')