pl / sql游标处理和输出

Question

  

这是我试图开始工作的下面的代码（PL / SQL）。结果是按名称（product_name）列出所有产品，并列出需求状态＆＃39;列显示“需求低”＆＃39;或者“需求量大”＆＃39;根据订购的产品数量。 （如果数量> 2 =高）这是第一次使用匿名块。

    My results are as follows (with just a snip) and what it should show is followed after that.

My results:   
Product Name            Demand Status
---------------     ---------------------
Intermediate Ski Boot         Low Demand
Product Name            Demand Status
---------------     ---------------------
Pro Ski Pole         Low Demand
Product Name            Demand Status
---------------     ---------------------
Intermediate Ski Boot         Low Demand
Product Name            Demand Status
---------------     --------------------

Correct results: 
Product Name Demand Status
------------ -------------
Beginner's Ski Boot Low Demand
Intermediate Ski Boot High Demand
Pro Ski Boot Low Demand
Beginner's Ski Pole Low Demand

Thank you for your help.  



declare
    demand_status varchar2 (10);
    quantity order_details.quantity%type;

    cursor p_cur is 
    select product_name
    from order_details, product
    where product.product_id = order_details.product_id;

    p_row p_cur%rowtype;

    begin
    open p_cur;
    loop
    fetch p_cur into p_row;
    exit when p_cur%notfound;
    if (quantity > 2 ) then demand_status := 'High Demand';
        else demand_status := 'Low Demand';
        dbms_output.put_line('Product Name'||'            '||'Demand Status');
    dbms_output.put_line('---------------'||'     '||'---------------------');
    dbms_output.put_line(p_row.product_name||'         '||demand_status);
        end if;
        end loop;

        close p_cur;
        end;