Re: automatic field creation

On Aug 27, 7:34 pm, Chris Brown <cbr...@xxxxxxxxxxxxxxxxxxxxxxxx>
wrote:
Diego B wrote:
I started studying relational DBs and FM specifically.

Now, the question: what is a flat file ? I am sorry for the basic
question but I really do not know.

The DB structure I implemented is something very well defined in many
clinical DBs I saw and asked about:

a central table with a primary natural key (the ID) and a surrogate
one (the clinical chart number, so that
I can talk with the clinical DBs here) where demographic information
about the patient is stored, and many other tables for the
examinations : Echocardiography,
genetics, biomarkers, clinical variables etc...
all the tables are related trough the primary Patient key (ID), then
each table has its own primary key, as a serial number.

If you think there is something wrong in this, please let me know, I
am ready to send you also the DB, or if you have
something you trust (preferably in FM) you could send me an empty DB
just to understand how to make it in the right way.

regards

Cheers !

Chris Brown- Hide quoted text -

Diego

Hi Diego,
it appears that yo do have a relational structure from the tables you
outline, and as Lynn also observes. How el that is implemented is
impossible to guess, without looking at the file(s).

Lynn and Chris, thank you very much for the support...now I know
I am going in the right direction and this makes me happy (I think
you can immagine how long time I spent designing and implementing
this DB, at the beginning I made so many mistakes...)



A flat file approach can also result within a single table. For
example, the Echocardiography table the keying would be something like:
patient_ID, EchoCard_ID, TestDate, and possibly TestLab_ID.


Now it is clear, I saw many flat files too, in access for example,
but
I did not know the correct name : )

What I have often seen is that people will create a set of fields to
record the data for a test or visit, and then replicate all those fields
for each subsequent test or visit or follow-up. So if there are 100
fields to record the results at a test/visit, and the patient comes in
every year for twelve years, then the table will end up with 100 x 12
fields. I have seen this on numerous occasions (several instances had
reached 15 years). This is what I thought may be happening, when you
originally referred to duplicating 300 fields.


Ok, fortunately I did not even think to implement something like that
sometimes you recognize how much lucky you are only afterwards...

Regards and thank you again, I will take advantage of all the advices
I got
here and keep upgrading my DB to obtain the best performance !

Diego

.