How Many Is To Many

  • Thread starter Thread starter Charles L. Phillips
  • Start date Start date
C

Charles L. Phillips

Hello,
I am developing an application with MS-Access 97, on a Windows NT 4.0
platform.
Is there a design (standard) limit to the number of fields in a table, or
should there be more tables and fewer fields. When should a designer create
more than 1 database for 1 application???
 
Charles,
The Help file tells you the limits for these kind of things.
But the std answer is that a table can have up to 255 fields.
However, good DB design usually keeps that number well under 50.
Most tables have less than 20. Some have 1 or 2.

The *relationships* between the tables are the critical part of the design.
Once you see a properly designe DB, you will "get it" right away.
The problem is trying to figure it out on your own can be a real struggle.
So feel free to do some research on relational DB design and practice with
some throw away sample DBs before starting a serious project. Also feel free
to post here.

A designer should *always* create more than 1 DB. (This is known as a split
DB.)
The tables are in one DB with all the relationships and indexes. (Back End
or BE)
The queries, forms, reports, code are all in the other DB. (Front End or
FE)

The tables in the BE are linked to the FE.

There are many advantages to this structure. Updating the FE and sending out
a new copy without losing any data is a big one. Less corruption is another.
 
Hello,
"Thank You" for that info. You hit the nail...
I have read "Designing Apps w/MS-Access 97, Access 97 Bible & Access 97 &
VBA", & they do talk about the standard, but none of them speak of a "good"
quality design.

So "Thanks" again...


Joe Fallon said:
Charles,
The Help file tells you the limits for these kind of things.
But the std answer is that a table can have up to 255 fields.
However, good DB design usually keeps that number well under 50.
Most tables have less than 20. Some have 1 or 2.

The *relationships* between the tables are the critical part of the design.
Once you see a properly designe DB, you will "get it" right away.
The problem is trying to figure it out on your own can be a real struggle.
So feel free to do some research on relational DB design and practice with
some throw away sample DBs before starting a serious project. Also feel free
to post here.

A designer should *always* create more than 1 DB. (This is known as a split
DB.)
The tables are in one DB with all the relationships and indexes. (Back End
or BE)
The queries, forms, reports, code are all in the other DB. (Front End or
FE)

The tables in the BE are linked to the FE.

There are many advantages to this structure. Updating the FE and sending out
a new copy without losing any data is a big one. Less corruption is another.
Click to expand...
 
Hi, Charles.

See Jeff Conrad's incredibly comprehensive post on the thread "Free Access
Training", 12/10/04 for a list of Access development web resources. In
particular, one of the references has many relational database models,
showing the table structures of various types of applications.

http://www.databaseanswers.com/data_models/index.htm

Hope that helps.
Sprinks

Charles L. Phillips said:
Hello,
"Thank You" for that info. You hit the nail...
I have read "Designing Apps w/MS-Access 97, Access 97 Bible & Access 97 &
VBA", & they do talk about the standard, but none of them speak of a "good"
quality design.

So "Thanks" again...
Click to expand...
 
Hello,
This is really great, "Thank You"...
There should be more sites likes this...
 
Back
Top