BorlandTalk.com

viana · Guest

hi,

just a little question : if i set a Tfield.visible := false, will it be fetched to the client side ? ie, i have a provider linked to a query, and set all clients of the query to visible = false. in this situation, no fields will be fetched ?

thanks,
viana

Bill Todd · Guest

The Visible propertie determines which columns will be displayed in a
DBGrid. It has no affect on whether a column is fetched from the server
or not.

--
Bill Todd (TeamB)

viana · Guest

hello bill,

thanks for you reply.

is there a way to not fetch a specific column to
the client side ?

thanks,
viana

"Bill Todd" <no (AT) no (DOT) com> wrote:

Bill Todd · Guest

If you do not want the data in a column do not include that column in
the SELECT clause of your SQL statement. Does that answer your question?

--
Bill Todd (TeamB)

Esteban Pacheco · Guest

I had the question a while ago, and i coudlnt find an answer so i start
including the columns on the SQL Statement as you suggest, but, what i
needed and i think viana needs is

For example to have a Select * From Employee, but, in the client side, being
able to just select four columns out of the 15 (example) that the sql
statement returns, the reason behind this is to avoid having to specify
different queries in the app server side just to satisfy the need of more or
less columns in the client fetch.

I tought originally, that by doing a (Ctrl +A) in the fields of the
TClientDataset and selecting only the desired columns from the available
ones, it will limit, the columns being fetch to the client side, but, that
wasnt the case.

It will be a lovely feature for sure.

Is there anything like that out there?

Thanks

Esteban Pacheco
http://estebanp.blogspot.com

"Bill Todd" <no (AT) no (DOT) com> wrote

Bill Todd · Guest

There is no way that I know of to limit the columns transferred from
the middle tier to the client. If the issue is controlling which
columns are visible in a grid you can set the Visible property of the
field objects on the client, however, that will still transfer all of
the data from the middle tier to the client. Transferring the data to
the client may require more traffic than changing the CDS.CommandText
property and running a SELECT that returns only the columns you want.

--
Bill Todd (TeamB)

Esteban Pacheco · Guest

That's fair enough for me, thanks Bill.

Kostas Terzides · Guest

I think that building persistent fields of provider.dataset (in
application server) (if an option) and not including the field we don't
want to be included, then it will not be fetched in client side, but may
be I am wrong.