sql - 用新条目更新表列

Question

我正在使用Oracle APEX，并且希望使用下表中的新值更新报告中的列。报告查询如下图所示。

TABLE  "VENDOR_ACCOUNT" 
(  "VEN_ACCOUNTID"      NVARCHAR2(10), 
   "VEN_REGNO"          NVARCHAR2(10), 
   "VEN_TXDATE"         DATE, 
   "VEN_INVOICE_REFNO"  NVARCHAR2(10), 
   "TOTALAMOUNT"        NVARCHAR2(10), 
   "IN"                 NUMBER(10,0), 
   "OUT"                NUMBER(10,0) 
) 

SELECT "VEN_ACCOUNTID" , 
       "VEN_REGNO" , 
       "VEN_TXDATE" , 
       "VEN_INVOICE_REFNO" , 
       "TOTALAMOUNT" , 
       "IN",
       "OUT",   
       "TOTALAMOUNT"+"IN" as "CREDIT",
       "TOTALAMOUNT"-"OUT" as "DEBIT"
FROM Vendor_Account;

所需方案:我想用 TotalAmount和 Debit更新 Credit列。新的 Debit或 Credit值必须在下一条记录的 TotalBalance列中显示。

Answer 1

您可以使用Oracle分析函数LAG:

Select "VEN_ACCOUNTID" , 
        "VEN_REGNO" , 
        "VEN_TXDATE" , 
        "VEN_INVOICE_REFNO" , 
        "TOTALAMOUNT" , 
        "TOTALAMOUNT" + lag("IN",1) over (ORDER BY "VEN_ACCOUNTID")
                      - lag("OUT",1) over (ORDER BY "VEN_ACCOUNTID") AS "NEW_TOTALAMOUNT",
        "IN",
        "OUT",  
        "TOTALAMOUNT"+"IN" as "CREDIT",
        "TOTALAMOUNT"-"OUT" as "DEBIT"
FROM    Vendor_Account;