Creating relationships on the backend part

[Amer]

Is there any difference between creating relationships on the tables in the
back-end part of the database and between creating them on the local part
(front-end)?

Which one is better? and why both don't automatically take the same
relationships plan?

 

[Rick Brandt]

Is there any difference between creating relationships on the tables in
the back-end part of the database and between creating them on the local
part (front-end)?

Which one is better? and why both don't automatically take the same
relationships plan?

The difference is that relationships in the front end don't actually
exist. What you see in the front end are just "lines on the screen".
Those lines can provide some documentation for your structures and they
can cause default join lines to appear when you create queries, but
that's about it.

You only have an actual relationship of any importance if it enforces
referential integrity and those can only be created in the back end.
Since multiple *different* front ends could connect to a single back end,
it only makes sense that the data rules must exist in the back end.

 

[Amer]

Thanks a lot

The difference is that relationships in the front end don't actually
exist. What you see in the front end are just "lines on the screen".
Those lines can provide some documentation for your structures and they
can cause default join lines to appear when you create queries, but
that's about it.

You only have an actual relationship of any importance if it enforces
referential integrity and those can only be created in the back end.
Since multiple *different* front ends could connect to a single back end,
it only makes sense that the data rules must exist in the back end.

 

[a a r o n _ k e m p f]

If Split FrontEnd / BackEnd seems too complex for you-- it is for me
also.

If you just moved to Access Data Projects then you would actually be
able to have _REAL_ Referential Integrity (through DRI and / or
triggers)

it's just not allowed with linked tables and Jet.

 

[Tony Toews [MVP]]

Thanks a lot

Please ignore Aaron Kempf's postings as he is monomaniacal on the
subject of SQL Server and ADPs.

Tony
--
Tony Toews, Microsoft Access MVP
Please respond only in the newsgroups so that others can
read the entire thread of messages.
Microsoft Access Links, Hints, Tips & Accounting Systems at
http://www.granite.ab.ca/accsmstr.htm
Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/

 

[Larry Linson]

If Split FrontEnd / BackEnd seems too complex for
you-- it is for me also.

I'd find that easy to believe.

If you just moved to Access Data Projects then you
would actually be able to have _REAL_ Referential
Integrity (through DRI and / or triggers)

ADPs have nothing to do with Referential Integrity. RI is a database engine
function, as is how RI is implemented.

it's just not allowed with linked tables and Jet.

That is simply a mis-statement, incorrect on the face of it. In the
database where the tables reside, the Relationships Window allows creating
relationships and specifying Referential Integrity as properties -- no
triggers to write, no database modeling programs to purchase to create the
triggers for you.

Both Jet and ACE (default database engines for Access) or various server
databases (including the MS SQL Server, which is the only database supported
by ADP) support relationships and referential integrity.

Larry Linson
Microsoft Office Access MVP

 

[a a r o n _ k e m p f]

RI _WORKS_ when you use ADP.
it doesn't when you use Jet (because of silly things like multiple jet
backends, etc)

So yes-- DRI is a great option for ADP.

For Jet, it's not enforceable, it doesn't work.

 

[David W. Fenton]

Please ignore Aaron Kempf's postings as he is monomaniacal on the
subject of SQL Server and ADPs.

And almost always wrong, even on the subject in which he claims
expertise.

 

[a a r o n _ k e m p f]

David;

you're so full of shit, you claim that ULS and Replication are still
available in Access 2007 (format).

I'm always right. You guys just can't handle the truth, because you're
in denial, because you have a small penis and you don't have enough
intelligence to learn a real database.

SQL Server is the worlds most popular database.

Jet is fucking roadkill.

-Aaron

 

[a a r o n _ k e m p f]

Jet doesn't support RI.

What about RI between the front end and the back end?

What about RI between different databases, on different servers?

What about 'do something when you have a RI violation' (triggers)