使用merge into 優化update

MERGE INTO DMS_CRC_EVENT_SD_TRANS t1 
USING DMS_CRC_JL_EVENT_BASIC t2
ON(
   to_char(t2.power_on_time,'yyyy-mm-dd')=to_char(t1.outage_end_time,'yyyy-mm-dd') AND
   to_char(t2.power_off_time,'yyyy-mm-dd')=to_char(t1.outage_start_time,'yyyy-mm-dd') AND
   t1.trans_code=t2.hangcardno AND  t2.crc_trans_id IS NULL
  )
when matched then  
 UPDATE SET t1.sd_outage_start_time=power_off_time,t1.sd_outage_end_time=power_on_time

 ,t1.is_sd_start_time_correct=2,t1.is_sd_end_time_correct=2;

 UPDATE DMS_CRC_EVENT_SD_TRANS t1 SET (t1.sd_outage_start_time,t1.sd_outage_end_time
 ,t1.is_sd_start_time_correct,t1.is_sd_end_time_correct)=
(SELECT  t2.power_off_time,t2.power_on_time,2,2
  from DMS_CRC_JL_EVENT_BASIC t2
WHERE t2.hangcardno=t1.trans_code
AND to_char(t2.power_off_time,'yyyy-mm-dd')=to_char(t1.outage_start_time,'yyyy-mm-dd')
AND to_char(t2.power_on_time,'yyyy-mm-dd')=to_char(t1.outage_end_time,'yyyy-mm-dd')
AND t2.crc_trans_id IS NULL) WHERE t1.is_sd_start_time_correct =1;