CREATE TABLE ORDERS ( ORDERSID NUMBER(10) PRIMARY KEY, ORDERSDate DATE, ORDERStatus VARCHAR2(20), TotalCost NUMBER(10,2), CustomerID NUMBER(10), FOREIGN KEY (CustomerID) REFERENCES CUSTOMER(CustomerID) ); 以group25作为密钥加密TotalCost

以下是使用group25作为密钥加密TotalCost的SQL语句：

CREATE TABLE ORDERS_ENCRYPTED (
    ORDERSID NUMBER(10) PRIMARY KEY,
    ORDERSDate DATE,
    ORDERStatus VARCHAR2(20),
    TotalCost_RAW NUMBER(10,2),
    TotalCost_ENCRYPTED RAW(200),
    CustomerID NUMBER(10),
    FOREIGN KEY (CustomerID) REFERENCES CUSTOMER(CustomerID)
);

INSERT INTO ORDERS_ENCRYPTED (
    ORDERSID, ORDERSDate, ORDERStatus, TotalCost_RAW, CustomerID
)
SELECT ORDERSID, ORDERSDate, ORDERStatus, TotalCost, CustomerID
FROM ORDERS;

UPDATE ORDERS_ENCRYPTED
SET TotalCost_ENCRYPTED = dbms_crypto.encrypt(
    UTL_I18N.STRING_TO_RAW(TO_CHAR(TotalCost_RAW), 'AL32UTF8'),
    dbms_crypto.HMAC(Utl_Raw.Cast_To_Raw('group25'), Utl_Raw.Cast_To_Raw('sha256'))
);

ALTER TABLE ORDERS_ENCRYPTED DROP COLUMN TotalCost_RAW;

这个SQL语句创建了一个名为ORDERS_ENCRYPTED的新表，其中包含与ORDERS表相同的列，但是将TotalCost列拆分为TotalCost_RAW和TotalCost_ENCRYPTED两个列。然后，使用SELECT语句将ORDERS表中的数据复制到ORDERS_ENCRYPTED表中，并在TotalCost_RAW列中保存原始的TotalCost值。接下来，使用dbms_crypto.encrypt函数将TotalCost_RAW值加密，并将结果保存在TotalCost_ENCRYPTED列中。最后，使用ALTER TABLE语句删除TotalCost_RAW列，以确保只有加密后的值存储在ORDERS_ENCRYPTED表中。