In a COBOL program, how do you perform a sort operation, including the sort file definition and the basic syntax and meaning of the SORT statement?

Introduction / Context:
Sorting data is a common requirement in business applications, and COBOL provides a built in SORT statement that integrates with system sort utilities. Rather than writing custom sorting loops, developers can describe the sort keys and the flow of input and output records. To use the SORT statement correctly, you must define a sort file and understand the meaning of clauses such as USING, GIVING, and INPUT PROCEDURE.

Given Data / Assumptions:

• The program needs to sort records based on one or more keys, in ascending or descending order.
• A system sort utility is available and invoked under the covers by the COBOL runtime.
• The Data Division includes an SD entry that describes the logical sort file record layout.
• The SORT statement can either use existing files or procedures to supply and receive records.

Concept / Approach:
In COBOL, sorting is typically set up by defining a sort file in the Data Division with an SD entry that specifies the record structure. The SORT statement then names this sort file and defines sort keys using ON ascending KEY or ON descending KEY clauses. You can provide input records either through USING clauses that reference file names or through an INPUT PROCEDURE that reads records and releases them to the sort. Sorted records can be returned through GIVING clauses that specify output files or through an OUTPUT PROCEDURE that returns sorted records to the program via RETURN statements.

Step-by-Step Solution:
Step 1: Create an SD entry for the sort file in the Data Division and define the record layout, including fields that will serve as sort keys. Step 2: Code a SORT statement that references the sort file name and specifies ON ascending or descending KEY clauses for the relevant fields. Step 3: Supply unsorted records to the sort either by USING one or more input files or by writing an INPUT PROCEDURE that reads and RELEASEs records to the sort. Step 4: Direct sorted output either to files named in GIVING clauses or to an OUTPUT PROCEDURE that uses RETURN to receive sorted records for further processing.

Verification / Alternative check:
COBOL reference manuals show examples of SD entries, SORT statements, and associated INPUT PROCEDURE and OUTPUT PROCEDURE logic. These examples consistently use the pattern of SD definition, ON KEY clauses, and either USING or INPUT PROCEDURE plus GIVING or OUTPUT PROCEDURE. There is no requirement to write manual bubble sort loops, nor does COBOL require a CALL to an external CICS program to sort data. This confirms that the correct option is the one describing SD plus SORT with ON KEY and USING or GIVING clauses.

Why Other Options Are Wrong:
Option B is wrong because although manual sorting is possible, it is not the standard or recommended approach and the language does provide a SORT verb. Option C incorrectly claims COBOL lacks a SORT statement, when in fact SORT is part of the language. Option D suggests that all sorts are defined only in JCL, which ignores program level SORT operations. Option E incorrectly claims that only numeric keys can be sorted, but COBOL supports both numeric and character keys for sorting.

Common Pitfalls:
Common pitfalls include misdefining the SD record so that sort keys do not align with actual data, forgetting to specify ascending or descending order correctly, and confusing USING or GIVING with INPUT PROCEDURE or OUTPUT PROCEDURE. Another issue is not providing adequate JCL sort work files, which can cause runtime failures even if the COBOL code is correct. Understanding the relationship between SD entries, SORT clauses, and JCL definitions allows you to implement robust and efficient sorting in COBOL programs.

Final Answer:
You define a sort file with an SD entry and use the SORT statement with ON ascending or descending KEY and WITH INPUT PROCEDURE or USING plus WITH OUTPUT PROCEDURE or GIVING to control where records come from and where sorted records go