Further Reading — Chapter 4: Data Description Mastery

IBM Documentation

  • Enterprise COBOL for z/OS Language Reference — Chapter on "Data Description Entry." The definitive reference for every clause discussed in this chapter. Available free at the IBM Documentation website.

  • Enterprise COBOL for z/OS Programming Guide — "Defining Data" section. Provides practical guidance on storage allocation, alignment, and performance implications of USAGE choices.

  • IBM z/Architecture Principles of Operation — Chapter on "Packed Decimal Instructions." For readers who want to understand exactly how the hardware executes COMP-3 arithmetic.

Textbooks

  • Stern, N., Stern, R., & Ley, J. COBOL for the 21st Century, 11th Edition. John Wiley & Sons. — Chapter on the DATA DIVISION provides excellent coverage of PICTURE clauses with many examples.

  • Brown, G. D. Advanced COBOL for Structured and Object-Oriented Programming, 3rd Edition. John Wiley & Sons. — Deep coverage of REDEFINES, OCCURS DEPENDING ON, and complex record layouts.

  • Murach, M. Murach's Mainframe COBOL. Mike Murach & Associates. — Practical, example-driven coverage of data description with a focus on enterprise patterns.

Online Resources

  • GnuCOBOL Programmer's Guide — Open-source COBOL compiler documentation. Covers data description with notes on differences from Enterprise COBOL. Free at gnucobol.sourceforge.io.

  • IBM Z Xplore — Free hands-on learning platform for mainframe development. Includes exercises on data description and record layout design. ibm.com/it-infrastructure/z/education/zxplore

Articles and Papers

  • Garfunkel, J. "Record Layout Design Patterns in COBOL." — A practitioner's guide to designing maintainable record layouts, with patterns for variant records, audit trails, and versioning.

  • "EBCDIC, Packed Decimal, and Binary: Understanding Mainframe Data Formats." IBM Developer. — Essential reading for understanding how DISPLAY, COMP, and COMP-3 data is physically represented on z/OS.

Topics for Further Exploration

  • COBOL 2002/2014 enhancements: The newer standards add USAGE NATIONAL for Unicode, USAGE OBJECT REFERENCE for OO COBOL, and extended PICTURE symbols. If your shop uses a modern compiler, explore these additions.

  • DFSORT and ICETOOL: IBM's sort utilities can manipulate packed decimal, binary, and zoned decimal fields directly in JCL without COBOL. Understanding USAGE formats is essential for writing SORT control statements.

  • DB2 data type mapping: How COBOL PICTURE and USAGE map to DB2 column types (CHAR, DECIMAL, INTEGER, etc.) is covered in Chapter 27. Understanding data description is prerequisite to effective embedded SQL.