Are cascade updates neccessary when all your foreign keys are autonumbers?

[xwnoob]

Hi,

Even if your foreign keys are all autonumbers, it doesnt matter if you tick or do not tick the cascade update amiright? Since its not advised to change autonumbers/primary keys. I only know that its neccessary to tick the cascade delete so that you are able to delete the related records.

 

[SteveH2508]

Your foreign keys should not be autonumbers. Your Primary keys should and, in answer to your question, if you have an autonumber primary key then cascade updates are irrelevant.

 

[xwnoob]

Your foreign keys should not be autonumbers. Your Primary keys should and, in answer to your question, if you have an autonumber primary key then cascade updates are irrelevant.

SOrry i said it wrongly yea my foreign keys are numbers.. and the datatype is set to the same as the autonumber

 

[gemma-the-husky]

personally, i would NEVER use cascading updates or deletes

firstly, cascading updates implies that a PK has changed, requiring the same values in linked tables to be changed. I would tend to use an autonumber key, that would never require changing. BUt if you choose a different key to an autonumber, it should be something that would never change (ef, like a two-letterus state value)

secondly, cascading deletes involves deleting data that has probably taken a long while to capture. I would generally prefer to set a "dead data" flag, and keep the data - but even if I DID want to delete the linked data, I would probably do it manually (ie via code, but under my control) rather than automatically