Subject Re: [IBO] Re: Dynamic Master Detail SQL
Author Helen Borrie
At 02:55 PM 4/08/2007, you wrote:
> >Don't you have Nil in C++? "NULL" doesn't look right to me, at least
>from the POV of ObjectPascal....Nil means "nothing assigned". NULL
>means something different to me...
>NULL expands to an int zero or a long zero. Unused pointers are
>normally zeroed. There is no Nil that I know of.

Try it. It's Delphi for "unassigned object".

> > Do your controls know that they have to link through a different
>Not sure what you mean 2 grids stay linked to DataSource1
>and DataSource2..... it's only the DataSource property of IBOQuery2
>that we're playing with.....

The TDatasource provides datalinking between a dataset and
controls. How can it be that you mess around with the datasets and
don't touch the datasources? The detail dataset's Datasource
property has to point to the TDatasource that provides the
datalinking for the master dataset.

Another thing you might not have thought about is the persistent
Fields[] you materialise those (TFields etc.) in your
IDE? If so, your code will have to get rid of them as well....that
alone could account for a large part of your problems.