Newbie help

  • Thread starter Thread starter Clinton
  • Start date Start date
C

Clinton

Hi. I am setting up a database of electronic parts I have laying around.
What I would like to do is, when I'm entering data in forms, if I select
Capaicitor from a drop down field, have the capacitance value field show.
If I select Resistor, have the resistance value field show. Am I being
clear about this? Can it be done?
 
Hi Clinton,

To get the best out of Access needs careful thought. One of the key
principles is "don't store data in field names": i.e. if you've got a
field called "Capacitance" that is empty if the object is a resistor or
a coil, and another called "Resistance" and so on, you're probably
heading down the wrong track. For instance, if you wanted to include a
loudspeaker you'd need to add fields for "Impedance" and "Diameter".

For simple components you could probably use a table structure like this
ComponentID
ComponentType - e.g. "Resistor", "Capacitor", "Op Amp"
Value - the value in ohms, or whatever
Kind - e.g. "Electrolytic", "Carbon Film", "Wire Wound"
Rating - e.g. watts for a resistor, volts for a capacitor
GenericCode - for components such as op amps, voltage regulators
etc.

You could have lookup tables to populate comboboxes (dropdowns lists),
for instance one for ComponentType. It would then be possible to modify
the labels on the form depending on the choice of component type: e.g.
"ohm" or "uF".

But the first thing is to get the data structure right. The user
interface - forms and so on - comes after that.
 
Back
Top