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

On 2011/11/25 12:41 PM, Gary Choi wrote:

... 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?

When you need extra control over which fields get changed by a READ or CHAIN, a good way is to use data structures for the I/O operations.

D A_ds e ds extname(A : *input) qualified
D B_ds e ds extname(B : *input) qualified

read A a_ds
chain key B b_ds
eval-corr b_ds = a_ds
update B b_ds

I can't tell whether you are using RPG III or RPG IV, but this requires using RPG IV. If you have to use RPG III for some reason (???), you will have to have a TMP for every field, or you will have to use I specs to rename every field for one of the files, and then add MOVE operations to get the file A values into the file B fields.