DFSORT is a program you use to sort, merge, and copy information.
When you sort records, you arrange them in a particular sequence, choosing an order more useful to you than the original one.
When you merge records, you combine the contents of two or more previously sorted data sets into one.
When you copy records, you make an exact duplicate of each record in your data set.
Merging records first requires that the input data sets are identically sorted for the information you will use to merge them and that they are in the same order required for output. You can merge up to 100 different data sets at a time.
In addition to the three basic functions, you can perform other processing simultaneously:
1. You can control which records to keep in the final output data set.
2. You can parse, edit, and reformat your records before or after other processing.
3. You can sum numeric information from many records into one record.
4. You can create one or more output data sets for a sort, copy, or merge application.
5. You can perform various "join" operations on two files by one or more keys.
JCL Sort structue is as follows--
//STEP001 EXEC PGM=SORT,REGION=1024K,PARM=parameters //SYSOUT DD SYSOUT=* Output messages from SORT //SORTIN DD DSN=...,DISP=SHR Input if SORT request //SORTOUT DD DSN=... Output for SORT request //SORTOFxx DD DSN=... OUTFILE output data sets //SORTXSUM DD DSN=... Output eliminated by the SUM stm //SORTWKnn DD UNIT=SYSDA, Work files if SORT request //SYSIN DD * Control statement input data set sort control statements /*
Listed below the processing order of the sort control statements:
SORT/SUM or COPY
SORTIN - Input record
SKIPREC=n causes sort to skip over 'n' records in the input file before starting a sorting or copying operation.
INCLUDE - Include to the record for further process; OMIT - Exclude the record for further processinh
STOPAFT=n causes sort to stop after 'n' records in the input file have been sorted or copied.
INREC - It allows you to reformat the input records before they are sorted, merged, or copied.
SORT - Sort the record; SUM - Remove duplicate or sum the fields; COPY - copy the record.
OUTREC - It allows you to reformat the input records after they are sorted, merged, or copied.
OUTFIL - It allows you to create one or more output data sets.
SORTOUT - Output record
We wil see each sort control statements with examples in next chapter...
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