DFSORT - Omit duplicates with Input having 2 record types

[andrearak]

How can I sort the following file omitting duplicate records. There are 2 record types. In this file example I have the first four records are unique, the remaining 8 are duplicates of the first four. I need to maintain the order of the first four records and have the duplicates (last eight removed):

Currently using this, which is causing the correct recs to be written (no dups) just in ascending order, which is not desired:
SORT FIELDS=(1,500,A),FORMAT=CH
SUM FIELDS=NONE
END

Is there some command to skip every other record so that only the first four records are written in the existing order?

0000001405700100000000000TFS701F 0102010202
ADH_LOS-ANGELES_20090422_124744
0000001408900100000000000TFS701R 0102010281
ADH_LOS-ANGELES_20090427_140010
0000001405700100000000000TFS701F 0102010202
ADH_LOS-ANGELES_20090422_124744
0000001408900100000000000TFS701R 0102010281
ADH_LOS-ANGELES_20090427_140010
0000001405700100000000000TFS701F 0102010202
ADH_LOS-ANGELES_20090422_124744
0000001408900100000000000TFS701R 0102010281
ADH_LOS-ANGELES_20090427_140010

 

[MarcLodge]

Have a look at this doc:

http://www-947.ibm.com/systems/support/resources/sorttrck.pdf

It should provide you with what you are looking for.

Marc