Preventing duplicate data from multiple fields

[CTQE]

Hello All,

I'm trying to limit the data entered into a specifc field, but also the data must be unique with respect to other fields.

i.e.
Two fields: System A & System B.
Data entered into System A, can not be entered into System B.

Anyway to prevent this from recurring?
Would I use a validation rule?

Thanks in advance

 

[RuralGuy]

You may want to describe your table more completely. You may have a normalization issue to deal with.

 

[CTQE]

Okay, my goal is to use serial numbers. System A & System B are two different components (or parts). However, a serial number can only be used once across the board. So if I issue serial number 001 to a System A, that serial number (001) can not be used by any other part. I am generating a database from scratch so I'm not restricted by any other variables. Any suggestions or table format ideas that would solve this issue would be greatly appreciated.

Thanks for your quick response!!

 

[RuralGuy]

Consider a new record for each serial number in your table design.

 

[Mike375]

CTQE

If you have variation of the same type of data then it goes in the same field.

Think of LastName. You put all of those in the one field. Ditto for suburb, postcode etc.

Policy numbers for insurance all go in the same field.

Access loves to go "up and down" but gets all giddy with "across"