Re:Lookup fileds doesn't work with certain MDAC-versions
Hi Vassil,
Unfortunately, I didnt recognize your response from the 2nd of November
until now.
I am developing an application where I use ADOTables, Tdatasources,
TDBGrids, TDBNavigators and Access2000 database. Before I had no
relations in the database, but I introduced such after advices from the
newsgroup. The relevant part of my file structure is this:
Product Crop
/ / \
/ Batch CropRow
/ / \
Price BatchRow
The relationships shown are now also defined in the database. Before
they were only in the program. Master fields are specified in the
BetterADODataSets. The link is specified in the Field Link Designer.
These relations have always worked without problems.
However, I have two other relationship among the files that must be
handled.
1. Every BatchRow corresponds to a CropRow and there is certain
information on the CropRows that I need on the BatchRow. There is a
headline and there is information about slaes amounts. To retreive these
data, I define one Lookup field for the headline and one for sales
amount in the BatchRowDataSet. (Fields editor/Add field)
2. If a batch is sold the lookup field SalesAmount in the
BatchRowDataSet > 0. In the PriceDataSet I have a Lookup field where I
use this sales amount in the BatchRowDatSet to mark if there is
something to sell that week.
Relation no 2 has been the most difficult to get to work properly. It
only works with certain MDAC versions as far as I have seen. When it
doesnt work I dont get any data in my lookup fields. With the standard
ADO component, it also happened that wrong data was shown in the TDBGrid
connected to the PriceDataSet, probably because the Price-Batch
master-detail relationship failed in some way.
For the moment, everything works well on my developing machine, but I
can imagine thet I will get problems when the program shall be installed
by the clients.
Bengt H?kansson
Quote
Vassil Nazarov wrote:
> Bengt,
> What exactly do you mean by "lookup fields" and how do they fail?
> --
> Vassil Nazarov
> http://web.orbitel.bg/vassil/