Data Comparison Utilities

e.g., SuperC

Enhanced Definition

Data Comparison Utilities on z/OS are specialized software tools designed to identify and report differences between two datasets, members, or files. They are crucial for verifying data integrity, tracking changes, and aiding in problem determination by highlighting variances in content, structure, or attributes. A prominent example is the ISPF SuperC utility (`ISRSUPC`).

Key Characteristics

- Granular Comparison: These utilities perform comparisons at a detailed level, often line-by-line or record-by-record, identifying specific additions, deletions, or modifications.
- Comprehensive Reporting: They generate detailed reports that typically show the differing lines/records, their respective line numbers, and contextual information to facilitate analysis.
- Support for Diverse Data Formats: Capable of comparing various z/OS dataset organizations (e.g., PS, PDS/PDSE members, VSAM) and record formats (e.g., fixed, variable, undefined).
- Customizable Comparison Rules: Advanced utilities allow users to specify comparison criteria, such as ignoring specific columns, case sensitivity, leading/trailing blanks, or specific character strings.
- Interactive and Batch Modes: Many can be invoked interactively (e.g., via ISPF Option 3.12) for immediate analysis or executed in batch via JCL for automated processes.
- Return Code Indication: They typically set a return code (e.g., 0 for no differences, 4 for differences found) that can be used in JCL for conditional processing.

Use Cases

- Source Code Version Control: Comparing different versions of COBOL, PL/I, or Assembler source code members to identify changes between development iterations or releases.
- Configuration Management: Verifying that system configuration files (e.g., PROCLIB members, PARMLIB members) are consistent across LPARs or after applying system updates.
- **Data Validation and Auditing