在检查约束中使用日期,Oracle

Question

我试图检查添加以下约束,但Oracle返回如下所示的错误.

ALTER TABLE Table1
ADD (CONSTRAINT GT_Table1_CloseDate
CHECK (CloseDate > SYSDATE),
CONSTRAINT LT_Table1_CloseDate
CHECK (CloseDate <= SYSDATE + 365)),
CONSTRAINT GT_Table1_StartDate
CHECK (StartDate > (CloseDate + (SYSDATE + 730))));

错误:

Error report:
SQL Error: ORA-02436: date or system variable wrongly specified in CHECK constraint
02436. 00000 -  "date or system variable wrongly specified in CHECK constraint"
*Cause:    An attempt was made to use a date constant or system variable,
           such as USER, in a check constraint that was not completely
           specified in a CREATE TABLE or ALTER TABLE statement.  For
           example, a date was specified without the century.
*Action:   Completely specify the date constant or system variable.
           Setting the event 10149 allows constraints like "a1 > '10-MAY-96'",
           which a bug permitted to be created before version 8.

Answer 1

遗憾的是,检查约束不能引用像SYSDATE这样的函数.您需要创建一个触发器,在DML发生时检查这些值,即

CREATE OR REPLACE TRIGGER trg_check_dates
  BEFORE INSERT OR UPDATE ON table1
  FOR EACH ROW
BEGIN
  IF( :new.CloseDate <= SYSDATE )
  THEN
    RAISE_APPLICATION_ERROR( -20001, 
          'Invalid CloseDate: CloseDate must be greater than the current date - value = ' || 
          to_char( :new.CloseDate, 'YYYY-MM-DD HH24:MI:SS' ) );
  END IF;
  IF( :new.CloseDate > add_months(SYSDATE,12) )
  THEN
    RAISE_APPLICATION_ERROR( -20002, 
         'Invalid CloseDate: CloseDate must be within the next year - value = ' || 
         to_char( :new.CloseDate, 'YYYY-MM-DD HH24:MI:SS' ) );
  END IF;
  IF( :new.StartDate <= add_months(:new.CloseDate,24) )
  THEN
    RAISE_APPLICATION_ERROR( -20002, 
          'Invalid StartDate: StartDate must be within 24 months of the CloseDate - StartDate = ' || 
          to_char( :new.StartDate, 'YYYY-MM-DD HH24:MI:SS' ) ||
          ' CloseDate = ' || to_char( :new.CloseDate , 'YYYY-MM-DD HH24:MI:SS' ) );
  END IF;
END;

Answer 2

您不能在检查约束中使用SYSDATE.根据文件

检查约束条件不能包含以下结构:

• 子查询和标量子查询表达式
• 调用不确定的函数(CURRENT_DATE,
  CURRENT_TIMESTAMP,DBTIMEZONE,
  LOCALTIMESTAMP,SESSIONTIMEZONE,
  SYSDATE,SYSTIMESTAMP,UID,USER和USERENV)
• 调用用户定义的函数
• 取消引用REF列(例如,使用DEREF函数)
• 嵌套表列或属性
• 伪列CURRVAL,NEXTVAL,LEVEL或ROWNUM
• 未完全指定的日期常量

对于10g第2版(10.2),请参阅约束,对于11g第2版(11.2),请参阅约束.

请记住,完整性约束是关于表数据的声明,它始终为 true.

无论如何:我不确切地知道你想要实现什么,但我认为你可以使用触发器来达到这个目的.

Answer 3

每次记录更新时，SYSDATE都会具有不同的值。因此，约束每次都会不同地验证。因此，Oracle不允许在约束中使用sysdate。

您可以使用触发器来解决您的问题，该触发器检查CloseDate是否已实际更改，并在新值不在范围内时引发异常。

并且：什么是(StartDate > (CloseDate + (SYSDATE + 730))))？您无法添加日期。

并且：StartDate需要之后 CloseDate吗？那不奇怪吗？

Answer 4

Write sysdate into a column and use it for validation. This column might be your audit column (For eg: creation date)

CREATE TABLE "AB_EMPLOYEE22"
(
   "NAME"     VARCHAR2 ( 20 BYTE ),
   "AGE"      NUMBER,
   "SALARY"   NUMBER,
   "DOB"      DATE,
   "DOJ"      DATE DEFAULT SYSDATE
);

Table Created    

ALTER TABLE "AB_EMPLOYEE22" ADD CONSTRAINT
AGE_CHECK CHECK((ROUND((DOJ-DOB)/365)) = AGE) ENABLE;

Table Altered