difference between F and FB

roopannamdhari · New User Joined: 14 Sep 2006 Posts: 71 Location: Bangalore

Hi,

can anybody explain whats the difference between Logical record length parameter 'F'(Fixed) and 'FB'(Fixed block).

Gnanas N · Posted: Wed Mar 26, 2008 2:48 pm

F indicates that the records are fixed length...
FB indicates that the records are fixed length as well as blocked.

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arivazhagan_k · New User Joined: 05 Dec 2007 Posts: 57 Location: chennai

This may help you.

F (Fixed)

Fixed means that one physical block on disk is one logical record and all the blocks and records are the same size. This format is seldom used.

FB (Fixed Blocked)

This format designation means that several logical records are combined into one physical block. This format can provide efficient space utilization and operation. This format is commonly used for fixed-length records.

dick scherrer · Posted: Wed Mar 26, 2008 8:11 pm

Hello,

As this is posted in "cobol", how does this (F/FB) relate to cobol code?

I'm not sure how F and/or FB relate to Logical RECord Length (LRECL)?

If what has been posted does not answer your question, please clarify.

chituswain · New User Joined: 01 Apr 2008 Posts: 3 Location: PPT

Hi,

F indicates that the records are fixed length...
FB indicates that the records are fixed length as well as blocked.

Say for example, we have a file of LRECL 80 bytes and Blocksize is 8000.
That means 1 Block consists of 100 record. In real time when we are reading record from file in cobol program, it is called as I/O processing(Input/Output). TO avoid the no of I/O processing time, we are using the file that defined with FB.