SORT processing order for record handling, exits, statements, and options

The below diagram illustrates the processing order for record handling, exits, statements, and options.

Use this diagram with the text following it to understand the order DFSORT uses to run your job.

 

1. DFSORT first checks whether you supplied a SORTIN data set for SORT and COPY jobs or SORTINnn data sets for MERGE jobs. If so, DFSORT reads the input records from them.
   • If no SORTIN data set is present for a SORT or COPY job, you must use an E15 user exit to insert all the records. (This is also true if you invoke DFSORT from a program with the address of an E15 user exit in the parameter list, because SORTIN will be ignored.) DFSORT can use a COBOL E15 routine if you specified the E15 user exit in the MODS statement.
   • If no SORTINnn data sets are present for a MERGE job, you must use an E32 user exit to insert all the records.
2. If input records for SORT or COPY jobs are read from a SORTIN data set, DFSORT performs processing specified with the SKIPREC option. DFSORT deletes records until the SKIPREC count is satisfied. Eliminating records before a SORT or COPY gives better performance.
3. If the input records for a SORT or COPY job are read from a SORTIN data set, DFSORT checks whether you specified an E15 user exit. If so, DFSORT transfers control to the user exit routine. You can use a COBOL E15 routine if the E15 user exit is specified in the MODS statement. The E15 routine can insert, delete, or reformat records.
4. DFSORT performs processing specified on an INCLUDE or OMIT statement. If you used an E15 user exit routine to reformat the records, the INCLUDE/OMIT fields you specify must apply to the current format rather than to the original format. If you use the INCLUDE or OMIT statements to delete unnecessary records before SORT, MERGE, or COPY processing, your jobs run more efficiently.
5. For SORT or COPY jobs, DFSORT performs processing specified with the STOPAFT option. Record input stops after the maximum number of records (n) you specify have been accepted. DFSORT accepts records for processing if they are:
   • Read from SORTIN or inserted by E15
   • Not deleted by SKIPREC
   • Not deleted by E15
   • Not deleted by an INCLUDE or OMIT statement.
6. DFSORT performs processing specified in an INREC statement. Data records are parsed, edited and reformatted according to the options specified. If you reformatted the records before this step, the INREC fields you specify must apply to the current format rather than to the original format.
7. DFSORT performs processing specified in the SORT, MERGE, or OPTION COPY statement.
   • For SORT, all input records are processed before any output record is processed.
   • For COPY or MERGE, an output record is processed after an input record is processed.
   • For SORT or MERGE, if a SUM statement is present, DFSORT processes it during the SORT or MERGE processing. DFSORT summarizes the records and deletes duplicates. If you reformatted the records before this step, the SORT or MERGE and SUM fields you specify must apply to the current format rather than to the original format.
8. DFSORT performs processing specified in an OUTREC statement. Data records are parsed, edited and reformatted according to the options specified. If you reformatted the records before this step, the OUTREC fields you specify must apply to the current format rather than to the original format.
9. If an E35 user exit is present, DFSORT transfers control to your user exit routine after all statement processing (except OUTFIL) is completed. If you reformatted the records, the E35 user exit receives the records in the current format rather than in the original format. You can use a COBOL E35 routine if you specify the E35 user exit in the MODS statement. You can use the E35 exit routine to add, delete, or reformat records.

   If SORTOUT and OUTFIL data sets are not present, the E35 exit must dispose of all the records because DFSORT treats these records as deleted. (This is also true if you do not specify OUTFIL data sets and DFSORT is invoked with the address of an E35 user exit in the parameter list, because SORTOUT will be ignored.)

10. DFSORT writes your records to the SORTOUT data set, if present.
11. DFSORT performs processing specified in one or more OUTFIL statements, if present:
    • DFSORT performs processing specified with the STARTREC, SAMPLE, and ENDREC options. Record input for the OUTFIL data sets starts with the record indicated by STARTREC, ends with the record indicated by ENDREC, and is sampled according to the records indicated by SAMPLE.
    • DFSORT performs processing specified with the INCLUDE, OMIT, or SAVE option. Records are included or omitted from the OUTFIL data sets according to the criteria specified.
    • DFSORT performs processing specified with the ACCEPT option. Record processing ends when the ACCEPT limit is reached.
    • DFSORT performs processing specified with the PARSE, OUTREC (or BUILD), OVERLAY, FINDREP, IFTHEN, FTOV, VTOF (or CONVERT), VLFILL, VLTRIM, VLTRAIL and REPEAT options. Data records are parsed, edited, reformatted, converted and repeated according to the options specified.
    • DFSORT performs processing specified with the LINES, HEADER1, TRAILER1, HEADER2, TRAILER2, SECTIONS, NODETAIL, BLKCCH1, BLKCCH2, BLKCCT1 and REMOVECC options. Data records are reformatted and report records are generated for the OUTFIL data sets.
    • DFSORT performs SPLIT, SPLITBY, or SPLIT1R processing. Records are distributed among the OUTFIL data sets as evenly as possible.
12. DFSORT writes your OUTFIL records to the appropriate OUTFIL data sets.