I recently tried a small performance experiment in Suprtool using
     the GET command with a $LOOKUP .vs. the CHAIN command.  And the
     winner depends upon what is more important time or CPU usage.

     Please note that both of these jobs were streamed at the same
     time by the same person in the same queue. Also, both of these
     jobs used a TABLE (CHAIN used it as input for indexes, GET used
     it in the $LOOKUP).

     GET and $LOOKUP:
     IN=5587824, SEL=67, OUT=21. CPU=754. Wall-Sec=974.

     CHAIN:
     IN=377373, SEL=67, OUT=21. CPU=171. Wall-Sec=3880.

     As you can see the GET and $LOOKUP took a significant amount of
     CPU resources but took very much less time.  The CHAIN command
     was easier on the CPU but took about 4 times longer.

     Other things to point out.  The index with the CHAIN command was
     not the main index(unique)  but a secondary search index (non
     unique).  I do not know how these numbers would have been
     different if the index had been a main (unique) index.

     Just thought someone might find this interesting....


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  Barry Durand      "The opinions expressed in this
  Systems Engineer II    email are not necessarily the
  Gulf South Health Plans    opinions of my employer"
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