What is merge sort in JCL?

What is merge sort in JCL?

The JCL needed for a merge is the same as that for a sort, with the following exceptions: You do not need dynamic allocation of work data sets or SORTWKdd DD statements. Instead of the SORTIN DD statement, you use SORTINnn DD statements to define the input data sets.

How do you use SUM fields in sort?

JCL – SORT SUM Fields The SUM control statement specifies that, whenever two records are found with equal sort or merge control fields, the contents of their summary fields are to be added, the sum is to be placed in one of the records, and the other record is to be deleted.

What is sort fields copy in JCL?

You can use SORT FIELDS=COPY or MERGE FIELDS=COPY instead of OPTION COPY to produce the same results. Summary. In this chapter, you covered the following concepts: Writing the SORT, COPY, or MERGE program control statements. Using JCL statements to process your sort, copy, or merge.

How do I merge two datasets in JCL?

JCL for merging data sets directly

  1. You do not need dynamic allocation of work data sets or SORTWKdd DD statements.
  2. Instead of the SORTIN DD statement, you use SORTINnn DD statements to define the input data sets. The SORTINnn DD statements name the input data sets, and tell how many data sets will be merged.

What is concatenation in mainframe?

The system can retrieve two or more data sets and process them successively as a single sequential data set. This is called sequential concatenation. The number of data sets that you can concatenate with sequential concatenation is variable.

How do you sort two fields in JCL?

You can further sort the records in the bookstore data set by specifying multiple control fields. When you specify two or more control fields, you specify them in the order of greater to lesser priority. Note that control fields might overlap or be contained within other control fields.

How do I sort fields in JCL?

JCL – SORT SORT Fields. The SORT control statement must be used when a sorting file is performed. This statement describes the control fields in the input records on which the program sorts. A SORT statement can also be used to specify a copy records. If multiple positions of sorting specified, the order of priority is from left to right.

How do I reformat an input field in JCL?

JCL – SORT OUTREC Fields. The OUTREC control statement allows you to reformat the input records after they are sorted, merged, or copied. You can create the reformatted OUTREC records in one of the following ways using unedited, edited, or converted input fields.

When should I use the merge control?

The MERGE control statement must be used when a merge operation is to be performed; this statement describes the control fields in the input records on which the input data sets have previously been sorted. A MERGE statement can also be used to specify a copy application.

How to sort a record in input file by two fields?

Example 2: SORT a record in input file by two field. If you see input file, it has same employee name for more than one record (e.g. KALAIA, SRINIV). let us add another field in the sort field. so that the same employee name will be sorted again by employee id (field started at column 9 , its length is 3)