SQL语句优化和前端AJAX

连的orcale 想请教一下各位..这个SQL语句还有能优化的地方嘛..库里五六十万条记录+一张1100W条的表，加上前端传过来的条件也要20s+..查询结果返回的时候前端也已经异步返回了.查询结果不显示..

不知道有没有什么办法能让sql执行快一点，或者还是只能把前端ajax改成同步？

        SELECT
        CE.EQUIP_NUMBER AS devid,
        CE.ENCURBANDISTRICT,
        CE.ENCREGION,
        CE.ENCBANK,
        CE.ENCDOT,
        se.TOTALDEPOSITAMOUNT,
        se.TOTALWITHDRAWALAMOUNT,
        se.TOTALDEPOSITLONGSHORT,
        se.TOTALWITHDRAWALLONGSHORT,
        to_char(to_date(se.EXDATE,'yyyy-mm-dd'),'yyyy-mm-dd')||' '||substr(se.EXTIME,0,2)||':'||substr(se.EXTIME,3,2)||':'||substr(se.EXTIME,5,2) AS nrdate,
        se.RZ100,
        se.RZ50,
        se.RZ20,
        se.RZ10,
        se.RZ5,
        se.RZ1,
        se.RY10,
        se.RY5,
        se.RY1,
        se.RCJ10,
        se.RCJ5,
        se.RCJ1,
        se.CZ100,
        se.CZ50,
        se.CZ20,
        se.CZ10,
        se.CZ5,
        se.CZ1,
        se.CY10,
        se.CY5,
        se.CY1,
        se.CCJ10,
        se.CCJ5,
        se.CCJ1 FROM
        CFG_EQUIPINFO CE inner join
        (SELECT
        s.*,ROWNUM RN from 
        (SELECT x1.*,
        row_number() over(partition by devid,to_char(to_date(x1.EXDATE,'yyyy-mm-dd'),'yyyy-mm-dd')||' '||substr(x1.EXTIME,0,2)||':'||substr(x1.EXTIME,3,2)||':'||substr(x1.EXTIME,5,2) order by to_char(to_date(x1.EXDATE,'yyyy-mm-dd'),'yyyy-mm-dd')||' '||substr(x1.EXTIME,0,2)||':'||substr(x1.EXTIME,3,2)||':'||substr(x1.EXTIME,5,2)) su 
        FROM
        SN_ENCEXCHANGEINFO  x1 where 1=1

        ) s
        ) se ON se.DEVID = CE.equip_number
        where 1 = 1
        and su=1