当用EXECUTE IMMEDIATE执行SQL语句中的参数个数也是动态的？用什么方法实现？
描述详细一点就是：在要执行的SQL语句中所用到(: parameter)这种参数的个数，因具体条件不同，而不同，而在执行语句EXECUTE IMMEDIATE中USING后边如何动态与前边的个数相匹配？
例子如下：
CREATE OR REPLACE PROCEDURE p_RentAreaCalcu
(pFloorId IN VARCHAR2, pBldgId in VARCHAR2,pRoomStyle IN VARCHAR2,
pAccountId IN VARCHAR2,pDateFrom IN DATE,pDateTo IN DATE,
pArea OUT NUMBER)
AS
/************************************************************
*功能: 出租面积计算组件 *
*参数：楼盘ID,楼宇ID,物业类型,客户,日期从,日期到
*返回值: 出租面积 *
*创建日期: 2002-11-19
*修改日期: 2002-11-19
*作者: xy *
*************************************************************/
v_SQL_Select VARCHAR(1000);
v_SQL_From VARCHAR(1000);
v_SQL_Where VARCHAR(1000);
v_SQL VARCHAR(3000);
v_Condition INTEGER; --跟踪SQL语句
e_DateNUll EXCEPTION; --错误变量
TYPE t_arr IS TABLE OF VARCHAR2(50) INDEX BY BINARY_INTEGER; --定义数组
v_Con_Arr t_arr; --保存查询参数
v_Month INTEGER; --DATEFROM与DATATO间隔的月的个数
BEGIN
--若DATEFROM与DATATO为NULL则引发错误
IF (pDateFrom IS NULL) OR (pDateTo IS NULL) THEN
RAISE e_DateNUll;
END IF;
-- 取得DATEFROM与DATATO间隔的月的个数
SELECT TRUNC(MONTHS_BETWEEN(pDateTo,pDateFrom),0)-1
INTO v_Month
FROM DUAL;
--加日期条件
v_Condition : = 0;
v_SQL_Select : =' SELECT '||
' SUM(TO_NUMBER(DECODE(SIGN(MONTHS_BETWEEN(: pDatefrom,a.begindate)),-1,'||'(TO_CHAR(LAST_DAY(a.begindate),''dd'')- TO_CHAR(a.begindate,''dd''))/TO_CHAR(LAST_DAY(a.begindate),''dd''),'||'(TO_CHAR(LAST_DAY(: pDatefrom),''dd'')- TO_CHAR(: pDatefrom,''dd''))/TO_CHAR(LAST_DAY(: pDatefrom),''dd'')))*b.leasearea +'|| 'b.leasearea*v_Month +'||
'TO_NUMBER(DECODE(SIGN(MONTHS_BETWEEN(: pDateto,a.finishdate)),-1,'||
'TO_CHAR(: pDateto,''dd'')/TO_CHAR(LAST_DAY(: pDateto,''dd''),'||
'DECODE(a.finishdate,'||
'NULL,'||
'TO_CHAR(: pDateto,''dd'')/TO_CHAR(LAST_DAY(: pDateto,''dd''),'||
'TO_CHAR(a.finishdate,''dd'')/TO_CHAR(LAST_DAY(a.finishdate,''dd''))))*b.leasearea)';
v_SQL_From : = ' FROM Lbs_conroom a,'||
' lbs_contract b';
v_SQL_Where : = ' WHERE UPPER(b.constatus) = ''PUB017002'''||
' AND b.excflag = ''1'''||
' AND a.begindate <= : pDateto'||
' AND (a.finishdate >= : pDatefrom or a.finishdate IS NULL';
--加楼盘ID条件
IF pFloorId IS NOT NULL THEN
v_Condition : = v_Condition + 1;
v_Sql_Where : = v_Sql_Where || ' AND b.mainfloor = : pFloorId';
v_Con_Arr(v_Condition) : = pFloorId;
END IF;
--加楼宇ID条件
IF pBldgId IS NOT NULL THEN
v_Condition : = v_Condition + 1;
v_Sql_From : = v_Sql_From ||',fm_bldginf c';
v_Sql_Where : = v_Sql_Where || ' AND b.mainfloor = c.floorid AND c.BldgId = : pBldgId';
v_Con_Arr(v_Condition) : = pBldgId;
END IF;
--加物业类型条件
IF pRoomStyle IS NOT NULL THEN
v_Condition : = v_Condition + 1;
v_Sql_Where : = v_Sql_Where|| ' AND b.roomstyle = : pRoomStyle';
v_Con_Arr(v_Condition) : = pRoomStyle;
END IF;
--加客户ID条件
IF pAccountId IS NOT NULL THEN
v_Condition : = v_Condition + 1;
v_Sql_Where : = v_Sql_Where ||' AND b.accountid = : pAccountId';
v_Con_Arr(v_Condition) : = pAccountId;
END IF;
--全部语句
v_SQL : = v_Sql_Select||v_Sql_Select||v_Sql_Where;
--得到出租面积
IF v_Condition = 0 THEN
EXECUTE IMMEDIATE v_SQL INTO pArea USING pDateFrom,pDateTo;
ELSIF v_Condition =1 THEN
EXECUTE IMMEDIATE v_SQL INTO pArea USING pDateFrom,pDateTo,v_Con_Arr(1);
ELSIF v_Condition =2 THEN
EXECUTE IMMEDIATE v_SQL INTO pArea USING pDateFrom,pDateTo,v_Con_Arr(1),v_Con_Arr(2);
ELSIF v_Condition =3 THEN
EXECUTE IMMEDIATE v_SQL INTO pArea USING pDateFrom,pDateTo,v_Con_Arr(1),v_Con_Arr(2),v_Con_Arr(3);
ELSIF v_Condition =4 THEN
EXECUTE IMMEDIATE v_SQL INTO pArea USING pDateFrom,pDateTo,v_Con_Arr(1),v_Con_Arr(2),v_Con_Arr(3),v_Con_Arr(4);
END IF;
--failure
EXCEPTION
WHEN e_Datenull THEN
ROLLBACK;
pArea : =NULL;
WHEN OTHERS THEN
ROLLBACK;
pArea : =NULL;
END p_RentAreaCalcu;
****************
特别说明：
原来我是照上边那样做的，最后发现不行，因为在SELECT语句中有几个DECODE函数，会用到参数，而用到参数的个数，根据数据的实际情况会有所不同，故我下边的EXECUTE IMMEDIATE语句中USING子句后的参数没办法写？怎样才能根据实际的条件自动匹配SELECT语句中用到的参数个数并且参数名称也匹配？
