RE: Indirect addressing databasefields

This has been covered before.  IT can be done, but it's tricky.  I think you
could use APIs and dynamic SQL to get the job done.  I started on something
like this, and actually got it working but found out that performance was
terrible.

My routine is something like this.  I write a subprocedure that accepts
parms:

#RtvValue(FileName:LibraryName:Member:FieldName:Key1:Value1:Key2:Value2:Key3
....)

Inside the #RtvValue subprocedure I build a dynimic SQL statement like
this...
----------
If (Member <> ' ')
 OvrDbf(file) to member(Member)
Endif

Select RRN(a), CHAR(A.FieldName) from LibraryName/FileName Where
Key1 = Value1, Key2 = Value2.... INTO :Value

RETURN Value
-------
This worked fairly well.  I even set up special keywords like *POS = Same to
read the same record by RRN to make it faster to retrieve values from the
same record, *NEXT to read after the last record, etc.  It always returned a
character value, though.

I don't have it into production, because I haven't worked with it for some
time.  But I was making some progress.

Brad

> -----Original Message-----
> From: Sven Mitscherlich [mailto:sms_mitschs@sms-as400.de]
> Sent: Tuesday, December 05, 2000 9:08 AM
> To: RPG400-L@midrange.com
> Subject: Indirect addressing databasefields
> 
> 
> Hello members,
> may I first intruduce me because this is my first post to this list.
> My name is Sven Mitscherlich, free consultant in the 
> IBM-Midrange-World, living in Germany ;-)
> 
> Now my question in the hope to get an answer:
> Is there any method available to indirect address a 
> databasefield, meaning the name of the databasefield is 
> stored in a variable.
> 
> I do not want to code a huge (and badly maintenable) 
> select-group. What I want is a method of flexibly 
> changeable rules to modify data using them.
> 
> Any advice is much appreciated.
> 
> Greetings from Germany
> 
> 
> Sven Mitscherlich
> SMS - System-Management-Software
> 
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