关于oracle pl/sql 动态SQL

 --差旅费用值变化时 同步更新报销模块的差旅费用值（税率值更新由前台方法实现同步）。                   
  procedure UPDATE_EMAMOUNT(p_tenantid number, p_mainid in number) IS
    tm_amount    decimal(10,2); --差旅费用值
    em_formula   varchar2(200); --率费计算公式
    em_tax      decimal(10,4); -- 税费
    em_expenseid number; --报销主表Id
    em_detailid  number; --报销明细ID       
  BEGIN
    --取差旅费用值
    select realamount
      into tm_amount
      from tm_travelmain t
     where TRAVELMAINID = p_mainid;
  
    --取报销明细ID
    select expensedetailid
      into em_detailid
      from em_expensetravel
     where travelmainid = p_mainid
       and tenantid = p_tenantid;
  
    --取报销主表ID
    select expenseid
      into em_expenseid
      from em_expenselist
     where expensedetailid = em_detailid;
  
    --取税率值
    EXECUTE IMMEDIATE 'select replace(taxformula,''总额'',''' ||
                      to_char(tm_amount) ||
                      ''') from  em_itemtypetax where itemtypeid= 
 (select itemtypeid from em_item where itemid= 
 (select expenseitemid from em_expenselist where  expensedetailid=' ||
                      em_detailid || '))'
      into em_formula;
   -- dbms_output.put_line(em_formula);
    EXECUTE IMMEDIATE 'select round(' || em_formula || ',4) rate from dual'
      into em_tax;
   -- dbms_output.put_line(em_rate);
  
  
    --更新报销明细表差旅费用及税额
    update em_expenselist
       set amount = tm_amount,taxamount=em_tax
     where expensedetailid = em_detailid;
  
    --更新报销主表中费用及税额
    update em_expensemain
       set amountsum = (select sum(amount)
                          from em_expenselist
                         where expenseid = em_expenseid),
                         businesstax = (select sum(taxamount)
                          from em_expenselist
                         where expenseid = em_expenseid)
     where expenseid = em_expenseid;
  END;

--调用1：
DECLARE   
mainid number;
tenantid number;
BEGIN   
mainid := 94;  
tenantid := 41;
pkg_tm.update_emamount(tenantid,mainid); 
END;

--调用2：
begin
  -- Call the procedure
  pkg_tm.update_emamount(p_tenantid => 41,
                         p_mainid => 94);
end;