Question Regarding '=ColumnHistory'

[David]

Hi,

Sorry for all the questions but I have embarked on building a database in
Access which is fully customized to our business requirements, I do not have
a massive knowledge of building databases but I am learning as I go and
asking a lot of questions.

My latest is regarding a notes and history field, I have seen this in some
of the working samples provided with Access and I am trying to duplicate the
code/mechanics. I have a table with a notes field and then I have copied the
history field from one of the working samples however when I put notes in to
the notes field the history field shows '#error', the code I am using is
=ColumnHistory([RecordSource],"Notes","[ID]=" & Nz([ID],0))

Could someone tell me what I am doing wrong or if this should work as I have
no idea at the moment how to resolve.

Thanks

 

[Douglas J. Steele]

To the best of my knowledge, there's never been a ColumnHistory function
built into Access, so it must be a user-written function in the sample
database. Without knowing more about it, it'll be pretty hard for any to
offer suggestions.

 

[David]

Sorry, I answered my own question, I just copied the fields from the working
sample form in to the form I needed.

Watch this space for the next question.

 

[BruceM]

I did some checking and was starting to get the impression there is a
ColumnHistory function (or maybe it's a property?) in Access 2007. Has
something to do with memo fields, from what I have been able to glean.

To the best of my knowledge, there's never been a ColumnHistory function
built into Access, so it must be a user-written function in the sample
database. Without knowing more about it, it'll be pretty hard for any to
offer suggestions.

--
Doug Steele, Microsoft Access MVP

(no e-mails, please!)

Hi,

Sorry for all the questions but I have embarked on building a database in
Access which is fully customized to our business requirements, I do not
have a massive knowledge of building databases but I am learning as I go
and asking a lot of questions.

My latest is regarding a notes and history field, I have seen this in
some of the working samples provided with Access and I am trying to
duplicate the code/mechanics. I have a table with a notes field and then
I have copied the history field from one of the working samples however
when I put notes in to the notes field the history field shows '#error',
the code I am using is =ColumnHistory([RecordSource],"Notes","[ID]=" &
Nz([ID],0))

Could someone tell me what I am doing wrong or if this should work as I
have no idea at the moment how to resolve.

Thanks

 

[Allen Browne]

I did some checking and was starting to get the impression there is a
ColumnHistory function (or maybe it's a property?) in Access 2007. Has
something to do with memo fields, from what I have been able to glean.

Yes: it's an A2007 thing, with memo fields where the AppendOnly property is
set.

 

[BruceM]

OK, thanks for the information. The sample database referenced by the OP
must have been in Access 2007.

 

[David W. Fenton]

Yes: it's an A2007 thing, with memo fields where the AppendOnly
property is set.

Does this mean they are actually stored as individual records? That
is, something like a multi-value memo field?

I'd not heard of this one. It certainly has promise to allow
inexperienced developers to create better memo fields, but
nonetheless, like multi-value fields, seems of little use to
experienced developers. Perhaps like multi-value fields, it was
included for SharePoint compatibility?

Are any experienced Access developers using SharePoint? I'm still
rather mystified as to what it is and what it can do (other than the
lame discussion boards/Intranet website stuff I've already seen),
and would be interested to know if developers with serious Access
chops are finding it useful, and what for.

 

[Allen Browne]

It does appear to be an MVF, David, and so I have not really investigated
it. If others are using it, we would love to hear from you.

Setting a memo's Append Only property to Yes seems to generate en entry in
MSysComplexColumns, where MVF info is stored.

 

[David]

Hi,

Thanks for all responses, as mentioned earlier I figured out the issue and
got it working.

Just to let you know, we use it as a form of traceability, if someone enters
a note in to a record it cannot be deleted from the history field by anyone.
This stops people from making notes that are not factual and concise.

As to how this works, I don't know my knowledge of Access is limited!

Regards

It does appear to be an MVF, David, and so I have not really investigated
it. If others are using it, we would love to hear from you.

Setting a memo's Append Only property to Yes seems to generate en entry in
MSysComplexColumns, where MVF info is stored.