Re: RPG400 same fields name of Input and Output files Update & Write question

(Editorial note: You are dealing with a butt trap. This process will come around and bite you right in the butt when you least expect it.)

Anyway, I think this is the operative thought on the issue: The fields will all have the value in them as-of the last record that was read. If you read file A and then chain to a record in file B and try to update file B values with File A values, you will have already overwritten the file A values with the File B values. Therefore you will update File B with the File B values. Your update will look like you've done nothing.

If this is an issue for you, you might wish to read about the prefix keyword for F-spec file names.

-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx [mailto:rpg400-l-bounces@xxxxxxxxxxxx]
On Behalf Of Gary Choi
Sent: Friday, November 25, 2011 11:41 AM
To: rpg400-l@xxxxxxxxxxxx
Subject: RPG400 same fields name of Input and Output files Update& Write
question

Hi,

I have a simply RPG with one Input file A, one output file B and they have
same fields names KEY, FIELD1, FIELD2

Here is the code:

*LOVAL SETLL A
1 DOWEQ 1
READ A 99
99 LEAVE

WRITE B


ENDDO

Without any MOVE (no rename of file B FIELD1& FIELD2) it can write to file
B

However, for update operation


*LOVAL SETLL A
1 DOWEQ 1
READ A 99
99 LEAVE

(MOVE FIELD1#TMP)

KEY CHAIN B 98
(MOVE #TMP FIELD1)

N98 UPDATE B


ENDDO

Without any MOVE in (...), can reading every records in file A update FIELD1
& FIELD2 in file B of the matching key of file B?
Further, if I add MOVE FIELD1 #TMP before CHAIN, and N98 MOVE #TMP FIELD1
after CHIAN, can it only update FIELD1 in file B with value of FIELD1 in
file A? and FIELD2 is unchanged in file B?


Thanks

CHOI
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