在做订单类似的系统都可能会存在订单编号不重复，或是流水号按日，按年，按月进行重新编号

可以参考以下存储过程

CREATE OR REPLACE procedure Pro_GetBillNO(TypeTable in varchar2,cur_mycursor out sys_refcursor) as DReceiptCode varchar2(40); DReceiptName varchar2(50); DPrefix1 varchar2(50); DISO varchar2(50); DIsAutoCreate varchar2(20); DPrefix2 varchar2(20); DPrefix3 varchar2(20); DDateValue date; DNO number; DLength number; DResetType number; DSeparator varchar2(20); DReturnValue varchar2(50); strsql varchar2(1000); begin DReturnValue:=''; select "ReceiptCode","ReceiptName","Prefix1","ISO","IsAutoCreate","Prefix2","Prefix3","DateValue","NO","Length","ResetType","Separator" into DReceiptCode,DReceiptName,DPrefix1,DISO,DIsAutoCreate,DPrefix2,DPrefix3,DDateValue,DNO,DLength,DResetType,DSeparator from "SysReceiptConfig" where "ReceiptCode"=TypeTable; if to_number(DResetType)>0 then if DIsAutoCreate=1 THEN if DResetType=1 then --按年份 if to_number(to_char(sysdate,'yyyy')) <>to_number(to_char(DDateValue,'yyyy')) then update "SysReceiptConfig" set "NO"=1,"DateValue"=to_date(sysdate) where "ReceiptCode"=TypeTable; else update "SysReceiptConfig" set "NO"="NO"+1 where "ReceiptCode"=TypeTable; end if; --年份 end if;--DResetType=1 if DResetType=2 then --按月份 if to_number(to_char(sysdate,'MM')) <>to_number(to_char(DDateValue,'MM')) then update "SysReceiptConfig" set "NO"=1,"DateValue"=to_date(sysdate) where "ReceiptCode"=TypeTable; else update "SysReceiptConfig" set "NO"="NO"+1 where "ReceiptCode"=TypeTable; end if; --月份 end if;--DResetType=2 if DResetType=3 then --按日 if to_number(to_char(sysdate,'dd')) <>to_number(to_char(DDateValue,'dd')) then update "SysReceiptConfig" set "NO"=1,"DateValue"=to_date(sysdate) where "ReceiptCode"=TypeTable; else update "SysReceiptConfig" set "NO"="NO"+1 where "ReceiptCode"=TypeTable; end if; --月份 end if;--DResetType=3 else update "SysReceiptConfig" set "NO"="NO"+1 where "ReceiptCode"=TypeTable; end if;--DResetType end if; strsql:=' select * from "SysReceiptConfig" where 1=1 '; strsql:=strsql ||' and "ReceiptCode"='''||TypeTable||''''; open cur_mycursor for strsql; end;