Transcript COBOL Unit 1

UNIT 1
Stephen S. Linkin
Houston Community College System
Graphics
Courtesy of IBM. And
Course Technologies
(Shelly and Cashman)
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Advantages of COBOL
Disadvantages of COBOL
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Stream input/output vs. record input/output
Blocking Records
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Step 1 - Understand the problem
Step 2 - Design the program
Step 3 - Code the program
Step 4 - Test the program
Step 5 - Document the program
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Top-down design/top-down programming
Divisions of a COBOL program
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IDENTIFICATION DIVISION
ENVIRONMENT DIVISION
DATA DIVISION
PROCEDURE DIVISION
ITERATION
SEQUENCE
CASE
ITERATION
SELECT
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A case study
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Hierarchy charts
Pseudocode
Flowcharts
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PROGRAM-ID
AUTHOR,
INSTALLATION,
DATE-WRITTEN,
and
DATE-COMPILED
Comment box
Format notation
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SELECT statements
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FILE SECTION
FD level indicator
◦ Level numbers
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Picture clauses
WORKING-STORAGE
SECTION
SWITCHES
ACCUMULATORS
Work area fields
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MAIN-PROGRAM
Initialization
Process-file
Process-record
Heading routine
Wrap-up
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Designing the Inventory Vendor Report
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Inventory Vendor Report
Hierarchy chart
Program flowchart
Inventory File record layout
Inventory Vendor Report program
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CONFIGURATION SECTION
SPECIAL NAMES
INPUT-OUTPUT SECTION
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Data categories
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Alphabetic (Text)
Alphanumeric (Mixed)
Numeric
Alphanumeric Edited
Numeric Edited
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Floating dollar signs
Plus sign
Minus sign
Credit symbol and debit symbol
Blank, zero, and slash
BLANK WHEN ZERO clause
JUSTIFIED RIGHT clause
Scaling — P symbol
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COBOL Field names must be unique
Qualified Names (Implied Duplication)
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