SQL，有关删除级联和有关更新级联 [英] SQL, On delete cascade and on update cascade

问题描述

我是SQL新手，遇到了一个奇怪的问题.所以我有两张桌子 供应商.这是供应商表.

I am new to SQL and I encountered a weird problem. So I have two tables OFFERS and SUPPLIER. Here is the Supplier table.

CREATE TABLE  "SUPPLIER" 
   (    "S#" NUMBER, 
    "NAME" VARCHAR2(50),  
    "CITY" VARCHAR2(50), 
     PRIMARY KEY ("S#") ENABLE
   )

这是OFFERS表.

CREATE TABLE  "OFFERS" 
   (    "P#" NUMBER, 
    "S#" NUMBER, 
    "V#" NUMBER, 
    "PR#" NUMBER, 
      CONSTRAINT "PK_OFFERS" PRIMARY KEY ("P#") ENABLE
   )

所以现在，当我尝试像这样向offers表添加外键约束

So now, when I try to add a Foreign key constraint to the offers table like this

ALTER TABLE OFFERS
ADD CONSTRAINT FK_SUPPLIERS FOREIGN KEY(S#)
 REFERENCES SUPPLIER (S#) 
ON DELETE CASCADE
ON UPDATE CASCADE

我收到一条错误消息:"ORA-01735:无效的ALTER TABLE选项".如果我删除最后一行，即"ON UPDATE CASCADE"，则可以正常工作.那么，我在做什么错呢?我在互联网上看到了很多类似的例子，这些例子本来可以工作，所以我有点困惑.如果有任何区别，我正在apex.oracle.com上工作.

I get an error saying : "ORA-01735: invalid ALTER TABLE option". If I remove the last line, which is "ON UPDATE CASCADE" this works perfectly fine. So, what am I doing wrong? I've seen a lot of examples like this on the internet, that are supposed to work, so I am kinda confused. I am working on apex.oracle.com if that makes any difference.

推荐答案

Oracle中没有更新级联":

There is no "on update cascade" in Oracle as far as I know (even in current versions):

http://asktom .oracle.com/pls/asktom/f?p = 100:11:0 ::::: P11_QUESTION_ID:5773459616034

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