求下部SQL优化，表的连接太多了_Oracle技术

求下面SQL优化，表的连接太多了。

SQL code

select a.id,            a.claimno ,            a.username ,            a.appealreason ,                        a.appealstatus,            a.appealResult,            b.tasksuggestion ,            b.updater ,            (select tasksuggestion from claimTasks  where tasktype='ZJPD' and taskid=a.claimno) ptasksuggestion            from             appealInfo a ,            claimTasks b            where              b.tasktype='SSPD' and  a.claimno=b.taskid and             appealFlag='1' and 1=1              order by id desc

目前执行时间太长了3.563s 2000多条数据

------解决方案--------------------
你这一行莫名其妙啊
(select tasksuggestion from claimTasks where tasktype='ZJPD' and taskid=a.claimno) ptasksuggestion

你到底想要什么功能啊
------解决方案--------------------

SQL code

SELECT A.ID,       A.CLAIMNO,       A.USERNAME,       A.APPEALREASON,       A.APPEALSTATUS,       A.APPEALRESULT,       B.TASKSUGGESTION,       B.UPDATER,       --   (select tasksuggestion from claimTasks  where tasktype='ZJPD' and taskid=a.claimno) ptasksuggestion        --以上相对占用资源，可改成decode的写法       DECODE(B.TASKTYPE, 'ZJPD', B.TASKSUGGESTION)  FROM APPEALINFO A, CLAIMTASKS B WHERE B.TASKTYPE = 'SSPD'   AND A.CLAIMNO = B.TASKID   AND APPEALFLAG = '1'   AND 1 = 1 ORDER BY ID DESC