RE: CHAIN Versus SETLL and READ When Data Needed

["Marvin Radding" <marvin.radding@xxxxxxxxxxxxxxxxxxxxx>]

> message: 1
> date: Wed, 28 Feb 2007 15:04:47 -0600
> from: "Lim Hock-Chai" <Lim.Hock-Chai@xxxxxxxxxxxxxxx>
> subject: RE: CHAIN Versus SETLL and READ When Data Needed 
>
> AFAIK, chain will not clear any data in the program when not found.
> With that say, I think chain is faster.  Since setll and read require
> two trips.  If chain is not found, it would be like setll. 

> From the manual:

When the CHAIN operation is successful, the file specified in name is positioned
such that a subsequent read operation retrieves the record logically following 
or
preceding the retrieved record. When the CHAIN operation is not completed
successfully (for example, an error occurs or no record is found), the file 
specified
in name must be repositioned (for example, by a CHAIN or SETLL operation)
before a subsequent read operation can be done on that file.


Just so no one is lead astray, if a CHAIN fails, the pointer is undefined and 
any read operation will results in an error.

Marvin