Oracle 年月比较

select distinct(dateColumn) from table where trunc(to_char(to_date('2005-8-1','yyyy-mm-dd'),'yyyymm')-to_char(dateColumn,'yyyymm'))=0

select distinct(dateColumn) from table where trunc(to_char(to_date('2005-8-1','yyyy-mm-dd'),'yyyy')-to_char(dateColumn,'yyyy'))=0