Re: SQL DESCRIBE was( SQLRPG - prepare, declare, no cursor) -- RPG400-L

There are different things you can do.

One thing you could do is to run a dynamically constructed SQL statementwith all the WHERE clauses that meet your fancy, and produce the outputfile from it that you can feed into your Prepare-Fetch statements. Youhave to build that file to feed into the SQL precompiler for embedded,but it might be worth it depending on requirements.

It might sound retrograde to some folks (anybody still use GSORT?), butit's a necessary technique in some cases to prevent grinding your systemto a halt if you get into some SQL statements.

A lot of users, if you let them get too many different Where scenariosinto one request, too, they can trip over themselves. Getting to manyAnd/Or's in the middle can give them plenty of confusion.

One of the things that will keep programmers in work into theforeseeable future.. :-)


--Alan

Hi Rick

It may seem a lot of work, it all depends on what you are trying to do.
I use SQL like this for powerful user driven search functions.
Constructing the WHERE clause can be tricky.
One limitation I found was to not push this technique too far.
I tried to construct a generic SQL so that it would work on any file.
I did not succeed because the SQL precompiler constructs data
structures based on the file it finds at compile time.
I tried to process the disk output of DSPJRN for any file that

was journalled. The journal captures file data in one big field in thejournal output and I tried to map that data into a DS based onthe journaled file. The SQL looked fine and everything compiled but

it just did not work as the DSPJRN output is different for each file.
This may be possible using SQL APIs or the DESCRIBE statement but
both of these techniques are beyond my present skill.

Does anyone know how to use the DESCRIBE SQL statement.

Regards
Frank Kolmann

date: Tue, 11 Apr 2006 17:34:41 -0400
from: "rick baird" <rick.baird@xxxxxxxxx>
subject: Re: SQLRPG - prepare, declare, no cursor

That's what I ended up doing - prepare-declare cursor-open-fetch-close.

I'm not ready to compile and test yet - many more subroutines to
write, but i think this is the ticket.
it does seem like an awful lot of work though, doesn't it?
thanks for the help.