如何在遊標循環中使用Trunc（mydate）

Question

我是PL/SQL的新手，並且今天正在處理遊標，並獲得了一個場景，我需要根據日期+金額+ cust_id獲取重複的交易類型+ txn_tpye。一旦我得到重複我不得不使用另一個遊標或使用選擇列值（日期+金額+ cust_id + txn_tpye）作爲where子句的正常循環。

在此之前，我只是試圖打印他們，如果我得到一個值或不，當我試圖打印mydate值出錯。請求你們的幫助。

SET SERVEROUTPUT ON 

declare 

CURSOR dup_check 

IS 

SELECT cust_id,amount,trunc(mydate),transaction_type,COUNT(1) 
FROM table_X WHERE trunc(mydate)>='10-OCT-2015' 
GROUP BY cust_id,amount,trunc(mydate),transaction_type 
HAVING COUNT(1)>1 ; 

BEGIN 

FOR UP_REC IN dup_check 

LOOP 

DBMS_OUTPUT.put_line(UP_REC.cust_id||' '||UP_REC.amount||UP_REC.trnasaction_type||**trunc(mydate))**; 

END LOOP; 

END; 


**PLS-00302: component 'mydate' must be declared** 

Answer 1

附加別名如下TRUNC（指明MyDate）領域，並把UP_REC.mydate在DBMS_OUTPUT

SET SERVEROUTPUT ON 
declare 
CURSOR dup_check 
IS 
SELECT cust_id, 
     amount, 
     trunc(mydate) mydate, /* add an alias here */ 
     transaction_type, 
     COUNT(1) 
FROM table_X WHERE trunc(mydate) >= '10-OCT-2015' 
GROUP BY cust_id,amount,trunc(mydate),transaction_type HAVING COUNT(1)>1 ; 

BEGIN 

FOR UP_REC IN dup_check 
LOOP 
DBMS_OUTPUT.put_line(UP_REC.cust_id||' '||UP_REC.amount||UP_REC.trnasaction_type||UP_REC.mydate)); 
END LOOP; 

END;