如何在PL/SQL中将每日快照转换为有效日期范围？

CREATE OR REPLACE PROCEDURE convert_snapshot_to_weekly
AS
   CURSOR c_snapshot IS
      SELECT snapshot_date
      FROM snapshot;

   v_snapshot_date snapshot.snapshot_date%TYPE;
   v_week_start    DATE;
   v_week_end      DATE;
BEGIN
   -- 遍历每日快照表中的日期值
   FOR rec IN c_snapshot LOOP
      v_snapshot_date := rec.snapshot_date;

      -- 计算每周范围起始日期和结束日期
      v_week_start := TRUNC(v_snapshot_date, 'IW');
      v_week_end := v_week_start + 6;

      -- 将转换后的日期范围和其他数据插入到新表中或返回查询结果
      -- INSERT INTO weekly_snapshot (week_start, week_end, other_columns)
      -- VALUES (v_week_start, v_week_end, other_values);

      -- 或者使用查询结果返回
      DBMS_OUTPUT.PUT_LINE('Week Start: ' || v_week_start || ', Week End: ' || v_week_end);
   END LOOP;
END;