double as id value

[alfalf]

Hello all.

I always used integer data type to store my IDs in tables design. Is it wise to use double data type (as 2,7 Bill is small array here due to fact that our id are not autonumbers, instead they're combination of four different IDs)? Does anyone have expirience with this issue?

Thanks for suggestions.

 

[cmmrfrds]

I would avoid using a double data type as it is a floating point number and approximate. This is not always reliable if you are comparing 2 numbers - especially a key.

see.

http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm

 

[mikey69]

A further point to consider is that it's unwise to choose keys which have other significance. An integer key which is used for nothing else is usually best.

Access makes all things possible. It even makes them intelligible

 

[willir]

alfalf

In past lives, when disk space at a premium, server memory was perhaps a whooping 16 MB, virtual memory was new a revolutionary, complex ways of storing and sorting data was used to save money and get the biggest bang for the buck.

However, these approaches would some times blow up leading to a mess. Also, it would take "work" to create the coded value, and "work" to decode the data.

...Moving On
Disk space is huge, size of memory is awesome, CPU's are lighting fast.

So the developers no longer worry about creating multipurpose fields -- why bother with the extra work unless there is a real good reason.

There is one good reason - encryption and data security.

Unless you have a real good reason, follow the rules of normalization and keep it simple....

Richard