CONTENTS

  Title Page

  Copyright Page

  Preface

  1      Introduction

  1.1     The Sample PARTS Database

  1.2     Overview of the Load Facility

  1.3     Overview of the Unload Facility

  1.4     Deciding Whether to Perform an Unload/Load Operation

  2      Loading a Database

  2.1     Load Facility Requirements

  2.2     How the Load Facility Operates

  2.3     Load Facility Components
    2.3.1      The Load Format Language File
      2.3.1.1      The LFL RECORD Entry
      2.3.1.2      The LFL ITEM Entry
      2.3.1.3      The LFL SET Entry
      2.3.1.4      Using the LFL WHERE Clauses
      2.3.1.5      Using the LFL IGNORE ORDER Clause
    2.3.2      The Load Sequence Language File
      2.3.2.1      LSL Sequence Name Entry
      2.3.2.2      LSL Sequence Record Entry
      2.3.2.3      LSL LOOP Entry
    2.3.3      The Subschema View
    2.3.4      The DBO/LOAD Command
      2.3.4.1      Example of DBO/LOAD Command

  2.4     Tips and Suggestions for Using the Load Facility

  2.5     General Approach to Loading a Database

  3      Unloading a Database

  3.1     Unload Facility Requirements

  3.2     Unload Facility Components
    3.2.1      The Subschema View
    3.2.2      The Load Format Language File
      3.2.2.1      The LFL RECORD Entry
      3.2.2.2      The LFL ITEM Entry
      3.2.2.3      The LFL SET Entry
    3.2.3      The Unload Sequence Language File
      3.2.3.1      USL Sequence Name Entry
      3.2.3.2      USL Sequence Record Entry
      3.2.3.3      USL Sequence LOOP Entry
    3.2.4      The DBO/UNLOAD Command
      3.2.4.1      Example of a DBO/UNLOAD Command
      3.2.4.2      Recovering an Unload Operation

  3.3     Using Unload for Data Extraction

  3.4     The Unload Buffers

  3.5     Tips and Suggestions for Using the Unload Facility

  3.6     Performing an Unload/Load Operation
    3.6.1      Set-Significant Information
    3.6.2      Sort Requirements of an Unload/Load

  4      The PARTS Database

  4.1     Loading the PARTS Database
    4.1.1      Writing the PARTS Load Definitions

  4.2     Unloading the PARTS Database

  4.3     Restructuring the PARTS Database
    4.3.1      Restructuring Rationale
    4.3.2      Steps in the Unload/Load Operation
    4.3.3      Changing the Schema
    4.3.4      Designing the Load Operation
      4.3.4.1      The LFL File
      4.3.4.2      The LSL File
      4.3.4.3      Sort Requirements
    4.3.5      Designing the Unload Operation
      4.3.5.1      The LFL File
      4.3.5.2      The USL File

  5      The SCHOOL Database

  5.1     SCHOOL Records, Sets, Insertion Modes

  5.2     Writing the SCHOOL Load Definitions

  A   PARTS Database Load/Unload Files

  A.1     PARTS LFL File
    A.1.1      RECORD Entries
    A.1.2      SET Entries

  A.2     PARTS LSL File

  A.3     PARTS USL File

  B   Restructuring PARTS Database Example Files

  B.1     The NEWPARTS Database
    B.1.1     NEWPARTS.DDL
    B.1.2     Creating the NEWPARTS Database

  B.2     Loading the NEWPARTS Database
    B.2.1     NEWLOAD.LFL
    B.2.2     NEWPARTS.LSL
    B.2.3     The DBO/LOAD Command
    B.2.4     SORT.COM

  B.3     Unloading the PARTS Database to Load the NEWPARTS Database
    B.3.1     NEWPARTS.LFL
    B.3.2     NEWPARTS.USL
    B.3.3     The DBO/UNLOAD Command

  C   SCHOOL Schema Definition

  D   SCHOOL Database Load/Unload Files

  D.1     SCHOOL LFL File
    D.1.1     RECORD Entries
    D.1.2     SET Entries

  D.2     SCHOOL LSL File

  D.3     SCHOOL USL File

  FIGURES

  1-1        You Must Identify Key Data Items During a Load

  4-1        Bachman Diagram of the PARTS Database

  4-2        Bachman Diagram of the NEWPARTS Database

  5-1        Bachman Diagram of the SCHOOL Database

  TABLES

  2-1        Summary of Load Facility

  2-2        LFL WHERE Clauses

  2-3        Effect of IGNORE ORDER Clause

  2-4        Sequence Record Entry Clauses

  3-1        Effect of the RELOAD ORDER Clause

  3-2        Unload Sequence Language Clauses