Oracle Trigger实例

create or replace trigger trigger_Twprecord_useDateTimebefore INSERT ON T_WPPRECORDfor each rowdeclarelast_datetime date;param_num number;BEGINselect RECTIME into last_datetime from T_WPPRECORD where rownum<=1 order by RECID desc;select PARAMNUMNAME into param_num from t_param_num where PARAMNUMID=2;--RAISE_APPLICATION_ERROR(-20001, to_char(:new.RECTIME,'yyyy-mm-dd hh24:mi:ss')||'test'||to_char(last_datetime,'yyyy-mm-dd hh24:mi:ss'));If ROUND(TO_NUMBER(sysdate - last_datetime) * 24)>=param_numTHENinsert into T_WPPRECORD_backup(RECID,RECTIME,STATUS,TOTALACTENERGY,TOTALREENERGY,TOTALACTLOAD,TOTALRELOAD,ACTPLANT,REPLANT,AREAACTENERGY,AREAREENERGY,RESERVED1,RESERVED2,WPPID) select RECID,RECTIME,STATUS,TOTALACTENERGY,TOTALREENERGY,TOTALACTLOAD,TOTALRELOAD,ACTPLANT,REPLANT,AREAACTENERGY,AREAREENERGY,RESERVED1,RESERVED2,WPPID from T_WPPRECORD where RECTIME<=last_datetime;delete from T_WPPRECORD where RECTIME<=last_datetime;END IF;END trigger_Twprecord_useDateTime;