Input Mask or Validation?

I need to set Primary key field so that user has to enter 2 Letters and 4
numbers as serial number for hardware. Do I use Input mask or Validation
rule? What would be the expression?

Thanks for help

Steve

This input mask will work:

LL0000

--
Arvin Meyer, MCP, MVP
http://www.datastrat.com
http://www.mvps.org/access
http://www.accessmvp.com


"k11ngy" wrote in message
...
I need to set Primary key field so that user has to enter 2 Letters and 4
numbers as serial number for hardware. Do I use Input mask or Validation
rule? What would be the expression?

Thanks for help

Steve

On Sat, 16 Jan 2010 01:31:01 -0800, k11ngy
wrote:

I need to set Primary key field so that user has to enter 2 Letters and 4
numbers as serial number for hardware. Do I use Input mask or Validation
rule? What would be the expression?

Thanks for help

Steve

Either would work; the input mask might be a bit friendlier, as the validation
rule message can be cryptic. Try a mask of

LL0000

and/or a validation rule

LIKE "[A-Z][A-Z]####"

--

John W. Vinson [MVP]

"Arvin Meyer [MVP]" wrote in message
...
This input mask will work:

LL0000

--
Arvin Meyer, MCP, MVP
http://www.datastrat.com
http://www.mvps.org/access
http://www.accessmvp.com


"k11ngy" wrote in message
...
I need to set Primary key field so that user has to enter 2 Letters and 4
numbers as serial number for hardware. Do I use Input mask or Validation
rule? What would be the expression?

Thanks for help

Steve

Hi Steve,

Personally, I would use a validation rule. Input masks are generally a
pain-in-the-butt to deal with. Try the following validation rule at the table
level (so that it will apply to any query or form that uses this table as a
record source):

LIKE "[A-Z][A-Z][0-9][0-9][0-9][0-9]"

Also, I would set a unique index [Indexed: Yes (No Duplicates) ] on this
field, but I would not set it as the primary key, simply because I have a
strong preference for using the meaningless Autonumber data type as a primary
key. A text-based primary key will require you to check off the Cascade
Update option for a relationship with enforced Referential Integrity, if you
later need to change the value of this field, and have that value cascaded to
related child records. If the field is only present in a parent table as a
uniquely indexed field, you are free to change it's value at any time in the
future, without having to deal with potential locks on related records that
other users may be editing, in a multiuser environment. More discussion on
Cascade Updates, he

http://www.granite.ab.ca/access/cascadeupdatedelete.htm


Tom Wickerath
Microsoft Access MVP
http://www.accessmvp.com/TWickerath/
__________________________________________

"k11ngy" wrote:

I need to set Primary key field so that user has to enter 2 Letters and 4
numbers as serial number for hardware. Do I use Input mask or Validation
rule? What would be the expression?

Thanks for help

Steve

PS. Don't forget to include the appropriate Validation Text, such as:

This field requires two letters followed by four numbers.

You might also set the Field Size to 6, and set a unique index as I
mentioned in my previous reply.


Tom Wickerath
Microsoft Access MVP
http://www.accessmvp.com/TWickerath/
__________________________________________

"Tom Wickerath" wrote:

Hi Steve,

Personally, I would use a validation rule. Input masks are generally a
pain-in-the-butt to deal with. Try the following validation rule at the table
level (so that it will apply to any query or form that uses this table as a
record source):

LIKE "[A-Z][A-Z][0-9][0-9][0-9][0-9]"

Also, I would set a unique index [Indexed: Yes (No Duplicates) ] on this
field, but I would not set it as the primary key, simply because I have a
strong preference for using the meaningless Autonumber data type as a primary
key. A text-based primary key will require you to check off the Cascade
Update option for a relationship with enforced Referential Integrity, if you
later need to change the value of this field, and have that value cascaded to
related child records. If the field is only present in a parent table as a
uniquely indexed field, you are free to change it's value at any time in the
future, without having to deal with potential locks on related records that
other users may be editing, in a multiuser environment. More discussion on
Cascade Updates, he

http://www.granite.ab.ca/access/cascadeupdatedelete.htm


Tom Wickerath
Microsoft Access MVP
http://www.accessmvp.com/TWickerath/
__________________________________________

"k11ngy" wrote:

I need to set Primary key field so that user has to enter 2 Letters and 4
numbers as serial number for hardware. Do I use Input mask or Validation
rule? What would be the expression?

Thanks for help

Steve

=?Utf-8?B?VG9tIFdpY2tlcmF0aA==?= AOS168b AT comcast DOT net wrote
in news
Input masks are generally a
pain-in-the-butt to deal with.

Everyone says this. I don't understand it. Input masks do things
that cannot be done otherwise without substantial coding. I see no
reason whatsoever not to use them where appropriate (although dates
are about the only type of data I use them for regularly).

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/

Hi David,

Try copying data from one source (say an e-mail message), and pasting it
into a text box on a form that includes an Input Mask. I don't know about
you, but I've found that this generally fails even if the data is in the
correct format for the mask. The mask work fine when typing data in, but I
seem to have lots of problems in the past trying to paste data in from the
clipboard.


Tom Wickerath
Microsoft Access MVP
http://www.accessmvp.com/TWickerath/
__________________________________________

"David W. Fenton" wrote:

=?Utf-8?B?VG9tIFdpY2tlcmF0aA==?= AOS168b AT comcast DOT net wrote
in news
Input masks are generally a
pain-in-the-butt to deal with.

Everyone says this. I don't understand it. Input masks do things
that cannot be done otherwise without substantial coding. I see no
reason whatsoever not to use them where appropriate (although dates
are about the only type of data I use them for regularly).

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/

On 16 Jan 2010 22:29:14 GMT, "David W. Fenton"
wrote:

Everyone says this. I don't understand it. Input masks do things
that cannot be done otherwise without substantial coding. I see no
reason whatsoever not to use them where appropriate (although dates
are about the only type of data I use them for regularly).

Hi David,

I have to disagree with you on using input masks for dates. I find
them very presumptuous. How does the developer know how I enter
dates? Maybe I use 2 digit years, maybe 4. Maybe I use slashes or
hyphens. Maybe I type "jan 16". Access handles all of this with *no*
coding. Input masks might make it easy for the developer, but not so
much for the user.

The only place I've seen a *possible* use for input masks is for SSN.
The format is consistent enough that they can be helpful. But even
then, I'd rather accept the SSN with or without hyphens, and then run
it through a quick cleanup, validation and hyphenation function.

Armen Stein
Microsoft Access MVP
www.JStreetTech.com

=?Utf-8?B?VG9tIFdpY2tlcmF0aA==?= AOS168b AT comcast DOT net wrote
in :

Try copying data from one source (say an e-mail message), and
pasting it into a text box on a form that includes an Input Mask.
I don't know about you, but I've found that this generally fails
even if the data is in the correct format for the mask. The mask
work fine when typing data in, but I seem to have lots of problems
in the past trying to paste data in from the clipboard.

Input masks are for typing. If you are pasting arbitrary data into
the field from the clipboard, and this is by design, then you
shouldn't use a date mask. That's not what they are for, so it's
fine not to use it in that case.

But it's not a flaw in input masks. Input masks do exactly what they
were designed to do, restrict typed input.

--
David W. Fenton http://www.dfenton.com/
usenet at dfenton dot com http://www.dfenton.com/DFA/