001、char----date
STR_TO_DATE(str,format)
1、分隔符一致
2、年月日对应
例如select str_to_date('09/01/2009','%m/%d/%Y')
select str_to_date('2008-4-2 15:3:28','%Y-%m-%d %H:%i:%s')
002、CAST(expr AS type), CONVERT(expr,type), CONVERT(expr USING transcoding_name)
select cast(now() as char);
select convert( '中文 ' using gb2312);
select date_add(now(),interval 1 day);