一段存储过程，请大家帮忙优化
CREATE PROCEDURE "loan".getpayschedule(dat date) returning varchar(255); define returnstr varchar(20); define v_duebillno varchar(20);--借据号 define v_maxcurrentno INTEGER;--最大期次 define v_duebno varchar(20); define v_sq INTEGER; define v_paydate varchar(20); define v_maturedate varchar(10); define count1 int; define v_gitid int;--自动id define v_currentnosc int;--提前还款上一次期次 define v_gitid1 int; define sql_err,isam_err int;--异常处理 SET DEBUG FILE TO "gittestcom.txt"; let sql_err = 0; TRACE ON; begin on exception set sql_err delete from Acc_PayScheduleTmp; delete from acc_payschedule; trace "sql_err--->"||sql_err; return "0"; end exception with resume ; delete from Acc_PayScheduleTmp; delete from acc_payschedule; --从核心中间表导入所需数据岛临时表 -- insert into Acc_PayScheduleTmp select ap.*,TO_CHAR(today,'%Y%m%d')||seqhkjh.NEXTVAL from Acc_PaySchedule1 ap,loanduebill ld where ap.duebillno=ld.duebillno; insert into Acc_PayScheduleTmp select contractno,duebillno,currentno,maturedate,currentsum,currentinterest,currentnormalinterest,currentoverdueinterest,currentoffsheetinterest,payoption,paydate,paysum,payinterest,currency,hexinappid,TO_CHAR(today,'%m%d')||seqhkjh.NEXTVAL from Acc_PaySchedule1 where duebillno in('000001000096011001','000001000167011001'); foreach select duebillno into v_duebillno from Acc_PayScheduleTmp --开始轮循单条借据 let count1=0; foreach select duebillno,currentno,paydate,maturedate,gitid into v_duebno,v_sq,v_paydate,v_maturedate,v_gitid from Acc_PayScheduleTmp where duebillno=v_duebillno if(v_sq==2) then--提前还款从2开始 let count1=count1+1; if(count1==2) then --如果第二次提前还款跟新状态 select max(currentno) into v_maxcurrentno from Acc_PayScheduleTmp where duebillno=v_duebno and currentno>=2 and gitid<v_gitid; foreach select currentno,gitid into v_currentnosc,v_gitid1 from Acc_PayScheduletmp where duebillno=v_duebno and gitid >v_gitid-1 update Acc_PayScheduleTmp set currentno=v_maxcurrentno+v_currentnosc-1 where duebillno=v_duebillno and gitid=v_gitid1; end foreach end if end if end foreach end foreach insert into acc_payschedule select contractno,duebillno,currentno,maturedate,currentsum,currentinterest,currentnormalinterest,currentoverdueinterest,currentoffsheetinterest,payoption,paydate,paysum,payinterest,currency,hexinappid from acc_payscheduleTmp; let returnstr="1"; end TRACE OFF; return returnstr;end procedure;