Comments on: Primary file

By: nuccio

nuccio — Thu, 03 May 2012 17:31:13 +0000

Post your “F” and “I” and first “C” spec, then we can explain method

Work with the “primary” files is very efficient, but it is of difficulty understanding, it depends how the primary key is defined, what breakups of level is desired to manage……

You must search RPGII cicle.

Bye

By: mdratwa

mdratwa — Thu, 03 May 2012 15:18:16 +0000

Sorry – I am a COBOL programmer. Many, many years ago – back on old RPG, if you did not enter a “K” for keyed, the file is read by arrival sequence. Not sure what the latest version of RPG handle the file, but I would think that is would be read by arrival sequence or by key. (Why not dup the file (in test lib) and copy a few dozen records and run the program and see how the file is read.)

By: philpl1jb

philpl1jb — Thu, 03 May 2012 02:44:50 +0000

This is a supported but mature subset of RPG.
It allows the creation of reports with no statements (C specs), although it can be used in conjunction with C specs.
It’s a powerful tool, almost a seperate language.

Some programmers swear by and others swear at it.
Phil

By: tomliotta

tomliotta — Wed, 02 May 2012 22:13:48 +0000

But can anyone let me know how these primary file is read? Can you explain what you mean by the word "how"? One answer is that the compiler inserts instructions to call the DB2 routines that read records into the compiled program. The DB2 routines perform the reads just like they would if you coded READ instructions into your program source. Another answer might show an example from SQL:

INSERT INTO TSTINSERT                                     
with t1 (num, nam) as (SELECT CUSNUM, LSTNAM from QIWS/QCUSTCDT)
 SELECT num, nam from t1

That will insert rows into a table named TSTINSERT by retrieving rows from IBM's example file in QIWS named QCUSTCDT. But "how" does it read records in order to get the values? In some sense, the answer is simply "It just does it. It doesn't matter how." Tom