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Introducing DB-123 A New Approach to Database Management Systems

Introducing DB-123 A New Approach to Database Management Systems. Thomas Schneider February 2004. Goals.

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Introducing DB-123 A New Approach to Database Management Systems

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  1. Introducing DB-123 A New Approach to Database Management Systems Thomas Schneider February 2004

  2. Goals Upwards compatible database management· Minimize costs for migrations · Maximize security for users· Do not loose already existing Meta-Information like Hierarchies, Repetitions, …

  3. a practical example –the Donauland Database… consider the following structures … 29 DL/I Databases with75 DL/I Segments and10 permanent VSAM KSDS Files6 permanent VSAM ESDS Files10 SQL-Tables which have to be migrated to a different Operating System and a different Database Management System

  4. a practical example –the Donauland Database… A „classical“ Database-Migration of the described Databases to another System would imply : 55 Download-Programs necessary 95 DB2-LOAD-Files !!! without regarding the problems of Data Integrityas well as 600+ Application Programs to be adapted ….

  5. DL/I --> DB2 Migration A „classical“ Database-Migration to another System would imply : • 75 new DB2-Tables necessary only for DL/I Migration (excluding VSAM-Files) !!! • all 75 DB2-Tables have to be downloaded from the HOST and uploaded to the new system at once.!

  6. DB123 –the DL/I DB2 Migration-Tool • Performs the Database DESIGN automatically • manual adaption of DESIGN possible • automatic insertion of new fields possible –for instance USER-ID and UPDATE-Date in all new tables

  7. DB123 –the DL/I DB2 Migration-Tool [2] • generates DOWNLOAD Programs [COBOL SOURCE and VSE JCL!] for unloading the DL/I databases • performs rigorous checks of all values • check NUMERIC fields for valid entries • check all DATE-fields for valid Dates • 000000 --> SQL NULL • 999999 --> SQL NULL • Character-Fields: no imbedded quotes allowed

  8. DB123 –the DL/I DB2 Migration-Tool [3] • generates COBOL HOST-Variables for SQL-interface • automatic update of the „old“ DL/I record COPY-books …add parent keys, USER-ID, LAST-UPDATE, …

  9. DB123 –the DL/I DB2 Migration-Tool [4] • generates COBOL procedures (inline code) for the varios access methods: • xxxGET - for keyed access (unique key given) • xxxNEXT - for SQL Cursor access (alle seq.) • xxxNWP - ‚next within parent‘ [Cursor defined by ‚logical parent‘] • xxxISRT - for INSERTs • xxxDELE - for DELETEs (with given key) • xxxUPDT - for Updates

  10. DB123: the advantages Take again the Donauland example – for 95 DB2-Tables in the Application • There are 95 * 6 = 570 subroutines/procedures • which have NOT to be developed manually and tested, but are generated automatically !

  11. DB-123 DESIGN: The DB2-Data-Base Designer • for each DL/I Segment and each VSAM KSDS-File a DB2-Table has to be created • following the rules of the ‚3rd Normal Form‘ The rules of the 3rd Normal Form are very simple – read on …

  12. DB-123 DESIGN: The First Normal Form • All parent DL/I primary keys must be added to the child records (in front of the existing fields) • All unique DL/I primary keys become primary keys of the DB2-table as well.

  13. DB-123 DESIGN: the Second Normal Form • If the key is still not unique, a sequence field (trigger) ora so called TIMESTAMPis added • Each DB2 table has now a unique key !

  14. Is the DESIGN now complete ? • NO ! • The DL/I Databases may contain OCCURS-items in the COBOL record structures!

  15. Is the DESIGN now complete ?…continued • Cobol-OCCURS-items are NOT supported by DB2!Solution with DB123 : either new, higher level TABLES (DB2DETAIL) or NUMBERING the respective DB2 columns (both Alternatives may be performed automatically, driven by proper clauses in the Data Dictionary).

  16. DB-123 DESIGN: the Third Normal Form • All Tables are flat tables (including logical parent keys) • Hierarchic relationship retained thru „Logical Parent“ relationships (LPARENT-clause) in data Dictionary.

  17. DB-123 DESIGN: the Third Normal Form • Repeated COBOL structures resolved thru DBDETAIL clause in Data Dictionary • New Data Dictionary used to GENERATE ACCESS functions and needed COPY-books.

  18. Thank You ! For all inquiries and more information please contactoffice@db-123.com

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