oracle中 我给出一个周数 用什么函数可以取出这周的开始日期和结束日期...答:select SUNDAY,SATURDAY from (select sunday.the_week,decode(sign(sunday.the_day-saturday.the_day),-1,sunday.the_day,sunday.the_day-7)sunday,saturday.the_day saturday from (select to_char(wwm,'WW') the_week,to_char(wwm,'D') the_daynum,wwm the_day from (select trunc(...