[comp.windows.x] RDBMS Portability Isses

rubi@lgc.com ( Ernest Rubi) (01/29/91)

Does anyone have any information, experiences, case studies, etc. 
on the issues of developing RDBMS-portable applications using 
embedded SQL and X-Windows? I am particularly interested in 
portability issues between Oracle and Ingres, with additional 
interests in Sybase and Informix. Ideally, I would like to be 
able to take a C program containg embedded SQL and X-Window calls, 
run it through the preprocesssor of whichever RDBMS, and have the 
expectation that the program will function the same regardless of 
the RDBMS. Given the constraints of an industry that has not yet 
achieved this degree of standardization, I am looking for insights 
on how to (as much as possible) effectively and efficiently create 
portable X-Windows applications that can run under multiple RDBMSs. 
I will summarize responses on the net if there is sufficient response 
and interest. Thanks in advance.
 
---
Ernest Rubi			Phone : (713) 579-4789
Landmark Graphics Corp.		Fax   : (713) 579-4814
333 Cypress Run			E-Mail: rubi@lgc.com
Houston, TX  77094

don@zardoz.coral.COM (Don Dewar) (02/04/91)

We have written an X-based program using X-Windows, Motif, and Ingres.
What we did to help insure portability was to completely separate the
X/Motif code and the Ingres code.  Since we are using g++, we created
p-objects (presentation objects) that implement the UI, and d-objects
(data objects) that access the database.  Every time a pobject needs
data it accesses a dobject.  What this means to us is that if we wrote
very unportable imbedded sql, we only have to change a few methods in
a couple of dobjects.  I guess I really have not answered you
particular question.  What I have told you is how we have written our
code to easily be able to rewrite it for other db's.  

The problem is that all the imbedded SQL I have seen is different from
database to database syntactically.  The SQL statements are the same
of course, but the means of identifying imbedded SQL can be different.



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