怎么写求季度累计求和SQL语句_Oracle开发

如何写求季度累计求和SQL语句
我想按照季度求和

当输入201002时求 01，02的和
当输入201006时求 04，05，06的和
当输入201008时求 07，08的和
以此类推...代码类似如下，但是这个语句出错
大家帮帮我怎么写这个SQL

Java code

   SELECT '200902' DATE_ID,       T_COPLAN.MANAGECOM_ID MANAGECOM_ID,       SUM(T_COPLAN."VALUE") VALUE   FROM T_COPLAN  T_COPLAN   WHERE T_COPLAN.DEPT_ID = 1   AND T_COPLAN.SUBJECT_ID = 1   AND length(T_COPLAN.DATE_ID) = 6   AND length(T_COPLAN.MANAGECOM_ID) = 4   AND(  case          when substr('200902',5,2) in ('01','02','03') then          to_date(T_COPLAN.DATE_ID, 'yyyymm') BETWEEN          to_date(substr('200902', 1, 4) || '01', 'YYYYMM') AND         to_date('200902', 'YYYYMM')         when substr('200902',5,2) in ('04','05','06') then          to_date(T_COPLAN.DATE_ID, 'yyyymm') BETWEEN          to_date(substr('200902', 1, 4) || '04', 'YYYYMM') AND         to_date('200902', 'YYYYMM')         when substr('200902',5,2) in ('07','08','09') then          to_date(T_COPLAN.DATE_ID, 'yyyymm') BETWEEN          to_date(substr('200902', 1, 4) || '07', 'YYYYMM') AND         to_date('200902', 'YYYYMM')         when substr('200902',5,2) in ('10','11','12') then          to_date(T_COPLAN.DATE_ID, 'yyyymm') BETWEEN          to_date(substr('200902', 1, 4) || '10', 'YYYYMM') AND         to_date('200902', 'YYYYMM')         end     )   group by T_COPLAN.MANAGECOM_ID

------解决方案--------------------

SQL code

SELECT '200902' DATE_ID, T_COPLAN.MANAGECOM_ID MANAGECOM_ID, SUM(T_COPLAN."VALUE") VALUE  FROM T_COPLAN T_COPLAN WHERE T_COPLAN.DEPT_ID = 1 AND       T_COPLAN.SUBJECT_ID = 1 AND       length(T_COPLAN.DATE_ID) = 6 AND       length(T_COPLAN.MANAGECOM_ID) = 4 AND       to_date(T_COPLAN.DATE_ID, 'yyyymm') BETWEEN trunc(to_date('200902', 'yyyymm'), 'Q') AND       last_day(to_date('200902', 'yyyymm')) GROUP BY T_COPLAN.MANAGECOM_ID
------解决方案--------------------
   SELECT '200902' DATE_ID,
      T_COPLAN.MANAGECOM_ID MANAGECOM_ID,
      SUM(T_COPLAN."VALUE") VALUE
  FROM T_COPLAN  T_COPLAN
  WHERE T_COPLAN.DEPT_ID = 1
  AND T_COPLAN.SUBJECT_ID = 1
  AND length(T_COPLAN.DATE_ID) = 6
  AND length(T_COPLAN.MANAGECOM_ID) = 4
 and (T_COPLAN.DATE_ID>=to_char(trunc(to_date('200902','yyyymm'),'q'),'yyyymm')
  and t_coplan.date_id<to_char(add_months(trunc(to_date('200902','yyyymm'),'q'),3),'yyyymm'))
group by T_COPLAN.MANAGECOM_ID