DB2 sql 上期（月、季、年）上月月末，上季末，上年末(统计中常用到)

SELECT

current timestamp -day(current  date) days ,-- 上个月月末 ,能够知道跨年

 

/*

to_date('2013-02-23','yyyy-mm-dd') -day(current  date) days ,-- 上个月月末 ,能够知道跨年

*/

 

CASE  WHEN  TO_CHAR('2012-06-22','Q') ='1' THEN  to_char(year('2012-12-01')-1)||'-12'
when  TO_CHAR('2012-06-22','Q') ='2' THEN to_char(year('2012-06-22'))||'-3'
when  TO_CHAR('2012-01-01','Q') ='3' THEN to_char(year('2012-12-01'))||'-6'
when  TO_CHAR('2012-01-01','Q') ='4' THEN to_char(year('2012-12-01'))||'-9'
 END AS tt , -- 上个季月 能够知道跨年

current date - (month(current date) -1 ) month - day(current date) day  --上年年末
 
 from sysibm.sysdummy1;