ABCs of z/OS System Programming Volume 3 - IBM Redbooks

DFSORT functions
DFSORT adds the ability to do faster and easier sorting, merging, copying, reporting and
analysis of your business information, as well as versatile data handling at the record, fixed
position/length or variable position/length field, and bit level. While sorting, merging, or
copying data sets, you can also:
► Select a subset of records from an input data set. You can include or omit records that
meet specified criteria. For example, when sorting an input data set containing records of
course books from many different school departments, you can sort the books for only one
department.
► Reformat records, add or delete fields, and insert blanks, constants, or binary zeros. For
example, you can create an output data set that contains only certain fields from the input
data set, arranged differently.
► Sum the values in selected records while sorting or merging (but not while copying). In the
example of a data set containing records of course books, you can use DFSORT to add up
the dollar amounts of books for one school department.
► Create multiple output data sets and reports from a single pass over an input data set. For
example, you can create a different output data set for the records of each department.
► Sort, merge, include, or omit records according to the collating rules defined in a selected
local.
► Alter the collating sequence when sorting or merging records (but not while copying). For
example, you can have the lowercase letters collate after the uppercase letters.
► Sort, merge, or copy Japanese data if the IBM Double Byte Character Set Ordering
Support (DBCS Ordering, the 5665-360 Licensed Program, Release 2.0 or an equivalent
product) is used with DFSORT to process the records.
DFSORT and ICETOOL
DFSORT has utilities such as ICETOOL, which is a multipurpose DFSORT utility that uses
the capabilities of DFSORT to perform multiple operations on one or more data sets in a
single step.
Tip: You can use DFSORT's ICEGENER facility to achieve faster and more efficient
processing for applications that are set up to use the IEBGENER system utility. For more
information, see z/OS DFSORT Application Programming Guide, SC26-7523.
DFSORT customization
Specifying the DFSORT customization parameters is a very important task for z/OS system
programmers. Depending on such parameters, DFSORT may use lots of system resources
such as CPU, I/O, and especially virtual storage. The uncontrolled use of virtual storage may
cause IPLs due to the lack of available slots in page data sets. Plan to use the IEFUSI z/OS
exit to control products such as DFSORT.
For articles, online books, news, tips, techniques, examples, and more, visit the z/OS
DFSORT home page:
http://www-1.ibm.com/servers/storage/support/software/sort/mvs
Chapter 4. Storage management software 191