referential integrity

sakfree · #1 (**permalink**) 10-02-07, 18:33

Can anyone give me an example why not to enable referential integrity in a relationship?

Thannk you.

r937 · #2 (**permalink**) 10-02-07, 19:11

um.....

as jerome howard once famously said, "i'm tryna think but nothin happens!"

georgev · #3 (**permalink**) 10-02-07, 20:28

Errrr.... You only have one table?

Pat Phelan · #4 (**permalink**) 10-02-07, 21:32

Quote:

Originally Posted by sakfree

Can anyone give me an example why not to enable referential integrity in a relationship?

You have already signed with another employer, and you bear GREAT ill-will toward your soon-to-be-former co-workers?

-PatP

sakfree · #5 (**permalink**) 10-04-07, 22:12

Quote:

Originally Posted by Pat Phelan

You have already signed with another employer, and you bear GREAT ill-will toward your soon-to-be-former co-workers?

-PatP

more details please, i don't understand your example

thanks

pootle flump · #6 (**permalink**) 10-05-07, 05:48

Relationships without integrity will never last and will leave you feeling a little dirty afterwards.

healdem · #7 (**permalink**) 10-05-07, 06:05

Quote:

Originally Posted by pootle flump

Relationships without integrity will never last and will leave you feeling a little dirty afterwards.

but just as equally relationships without integrity can also have their uses, in the absence of the integrity they may be good enough (or even as good) if you take adequate precautions

Ryker · #8 (**permalink**) 10-05-07, 07:15

Laziness?

(You didn't say good example.)

georgev · #9 (**permalink**) 10-05-07, 07:33

Quote:

Originally Posted by sakfree

Quote:

Originally Posted by Pat Phelan

You have already signed with another employer, and you bear GREAT ill-will toward your soon-to-be-former co-workers?

-PatP

more details please, i don't understand your example
thanks

that's genius!
Sakfree; Pat is basically saying to do it out of spite

Quote:

Originally Posted by pootle flump

Relationships without integrity will never last and will leave you feeling a little dirty afterwards.

Cynic

:hug:

Quote:

Originally Posted by healdem

but just as equally relationships without integrity can also have their uses, in the absence of the integrity they may be good enough (or even as good) if you take adequate precautions

See corral

Pat Phelan · #10 (**permalink**) 10-05-07, 09:05

Quote:

Originally Posted by sakfree

more details please, i don't understand your example

Think of creating a database without using referential integrity as a kind of "time delayed industrial sabotage" where you know that things will come to a crashing halt, but you're betting that they won't crash before you leave and that no one will realize that you are the culprit.

-PatP

Brett Kaiser · #11 (**permalink**) 10-05-07, 09:49

Are you guys kidding...I've seen so many damn 3rd party products that have none.

What the do is that they use the applicaion to enforce integrity...which in my opinion is a mistake

It means the database design is not fully thought out

But it is prevelant out there

I need to get another job

sakfree · #12 (**permalink**) 10-06-07, 19:41

http://office.microsoft.com/en-us/te...aspx?av=ZAC000

These are templates for access 2003, see the "Classroom management database" relationships

The relationship "Classes" and "Instructors"

mike_bike_kite · #13 (**permalink**) 10-06-07, 20:18

I've been working with financial databases for over 20 years - I've only ever come across a couple that had any mention of primary or foreign keys. I can only assume that nobody here produces databases for banks. To be fair though I can't think of a reason why they didn't have RI built in.

I was going to list a whole bunch of different design approaches that make it difficult to use foreign keys but I won't as I can't be arsed with the flaming I'll get.

Mike

andrewst · #14 (**permalink**) 10-07-07, 11:22

Quote:

Originally Posted by mike_bike_kite

I've been working with financial databases for over 20 years - I've only ever come across a couple that had any mention of primary or foreign keys. I can only assume that nobody here produces databases for banks. To be fair though I can't think of a reason why they didn't have RI built in.

Perhaps because they were built long ago when many DBMSs didn't actually support constraints, and nobody has decided to add them retrospectively? I can't imagine there is anything special about banking business that makes data integrity undesirable.

Quote:

Originally Posted by mike_bike_kite

I was going to list a whole bunch of different design approaches that make it difficult to use foreign keys but I won't as I can't be arsed with the flaming I'll get.

Go on, make our day

Actually, foreign keys aren't always the ideal constraint - the lack of support for more complex types of constraint sometimes forces database designers into adding spurious columns just so that a foreign key can be contrived to do the job.

r937 · #15 (**permalink**) 10-07-07, 11:27

Quote:

Originally Posted by andrewst

Go on, make our day

geez, tony, didja hafta?

well, i'm outta this thread...