RE: Dynamic Arrays

[Jim Langston <jlangston@xxxxxxxxxxx>]

Here here.  I learned that the hard way in one of the very first programs I did 
for someone (Under MS-DOS 2.0)
"How big do I need to make this array?  Are you absolutely sure it will never 
ever need more than 500 elements?  Positive?  Okay, I'll make it 5000 just to 
be sure.  Now, you're positive there will never be more than 500 elements?  
Okay."

6 months later I was back when the program was crashing when it was trying to 
load more than 5000 elements.  And somehow the source had disappeared.  So I 
wound up doing a kludge breaking the data up into 10 blocks so the program 
wouldn't crash anymore.

Ever since then, I never take the users word on anything having to do with data 
sizes, and I will try to never hardcode array sizes for user data.  You just 
never know.

Now, the problem Himasnhu, is that an array can only go up to 32767 (or 32766) 
records.  What is going to happen when some user tries to enter 32770 records?  
Your program is going to crash and burn, and you won't have a ready fix for it, 
other than kludging and using 2 arrays now, etc...

Best to just go the file, user space, etc.. route where you don't have a cap.

Regards,

Jim Langston

-----Original Message-----
From: Booth Martin [mailto:Booth@MartinVT.com]

ah!  yes, Himasnhu, you understand the problem perfectly!

As you do more in the AS/400 World you will come to realize that what you 
describe happening is very typical.  5 records today, 2,000 next year, 150 000 
five years from now.  Yes, nearly all of us would recommend  "Should I go for 
one more database file" solution because we have all seen sudden changes happen.

Think *NOMAX in all your planning.

-------Original Message-------

Booth,

A fine day I start coding one program, in which I am fetching records from 
database file and based on certain conditions I am storing in array to process 
in a batch.(Today I have only 5 records satisfying the criterion). what you 
feel. Should I go for one more database file to store all selected records if 
not what dimension I can choose for array ?? Say 500 but what about a year 
after when the selection criterion start selecting 1000 records. I feel only 
solution is REDIM array if possible with RPGLE.

Don't suggest any other way to store records like open query or something.. my 
requirement may be to use arrays only.

Himasnhu