計算列中的CASE語句問題

Question

我有一個SELECT語句，它工作正常，直到CASE部分，我認爲這只是一個語法錯誤和lead time位。我正在使用Oracle APEX。

我得到錯誤;

ORA-00923: FROM keyword not found where expected

select 
supplier.companyname as "Supplier", 
purchaseorder.orderdate as "Order Date", 
purchaseorder.duedate as "Due Date", 
popayment.datedelivered as "Delivered", 
(popayment.paymentdate - popayment.datedelivered) - 31 as paidontime, 

/* this is the same as the next one (this works fine) */ 
(popayment.datedelivered - purchaseorder.duedate) - 1 as deleiverylate, 

/* trying to advance the previous query (this does not work) */ 
popayment.datedelivered - purchaseorder.duedate -1, 
          case when "lead time" <0 then 'early' 
           when "lead time" >0 then 'late' 
           else 'on time' 
          end as "lead time"; 


from supplier, purchaseorder, suppliercontact, popayment 


where 
    purchaseorder.SUPPLIERCONTACTID2 = suppliercontact.suppliercontactid 
and 
    supplier.supplierid = suppliercontact.supplierid 
and 
    purchaseorder.purchaseorderid = popayment.purchaseorderid 

order by COMPANYNAME 

感謝所有幫助 危險布賴恩

Answer 1

刪除;這是你想要的嗎？

SELECT supplier.companyname        AS "Supplier", 
    purchaseorder.orderdate        AS "Order Date", 
    purchaseorder.duedate         AS "Due Date", 
    popayment.datedelivered        AS "Delivered", 
    (popayment.paymentdate - popayment.datedelivered) - 31 AS paidontime, 
    /* this is the same as the next one (this works fine) */ 
    (popayment.datedelivered - purchaseorder.duedate) - 1 AS deleiverylate, 
    /* trying to advance the previous query (this does not work) */ 
    CASE 
    WHEN popayment.datedelivered - purchaseorder.duedate -1 <0 
    THEN 'early' 
    WHEN popayment.datedelivered - purchaseorder.duedate -1 >0 
    THEN 'late' 
    ELSE 'on time' 
    END AS "lead time" 
FROM supplier, 
    purchaseorder, 
    suppliercontact, 
    popayment 
WHERE purchaseorder.SUPPLIERCONTACTID2 = suppliercontact.suppliercontactid 
AND supplier.supplierid    = suppliercontact.supplierid 
AND purchaseorder.purchaseorderid  = popayment.purchaseorderid 
ORDER BY COMPANYNAME 

Answer 2

你應該end as "lead time";