Transcript campus.murraystate.edu

Cobol
By: Steven Conner
Brief Understanding
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COBOL: COmmon Business Oriented
Language
Developed in 1960, still used today
Good for business programs but not app
programs
File Based Programming
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Has an input file for retrieving data
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Can do almost anything to this data.
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Sort, Organize, Calculate, Search and
Display/Edit/Remove, Add, Compare, Copy
Form
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Long programs are normally broken into
paragraphs
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Prevent retyping
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Should only call below
Variable
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Cobol doesn’t use variables it uses
PICTURE
PICTURE has three types A(alpha),
9(numeric), and X(alphanumeric)
Mathematical functions can only be done on
Legacy
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Cobol is still used in 80% of USA businesses
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Over 200 billion lines of code
Add Example
IDENTIFICATION DIVISION.
PROGRAM-ID. ADDREC.
ENVIRONMENT DIVISION.
FILE-CONTROL.
SELECT TRAN-FILE ASSIGN TO "STUDENT.TXT"
ORGANIZATION IS LINE SEQUENTIAL.
DATA DIVISION.
FILE SECTION.
FD TRAN-FILE
LABEL RECORDS ARE STANDARD.
01 TRAN-REC.
03 RNUM
PIC 999.
03 SFNAME PIC X(12).
03 SLNAME PIC X(12).
03 SDOBY
PIC 99.
03 SDOBM
PIC 99.
03 SDOBD
PIC 99.
03 SMNUM
PIC X(13).
WORKING-STORAGE SECTION.
01 REC.
03 RSFNAME PIC X(12).
03 RSLNAME PIC X(12).
03 RSDOBY
PIC 99.
03 RSDOBM
PIC 99.
03 RSDOBD
PIC 99.
03 RSMNUM
PIC X(13).
01 VAL PIC X.
PROCEDURE DIVISION.
BEGIN.
DISPLAY "First Name: " WITH NO ADVANCING.
ACCEPT RSFNAME.
DISPLAY "Last Name: " WITH NO ADVANCING.
ACCEPT RLFNAME.
DISPLAY "Date of Birth: Year: " WITH NO
ADVANCING.
ACCEPT RSDOBY.
DISPLAY "Month: " WITH NO ADVANCING.
ACCEPT RSDOBM.
DISPLAY "Day: " WITH NO ADVANCING.
ACCEPT RSDOBD.
DISPLAY "M Number: " WITH NO ADVANCING.
ACCEPT RSMNUM.
OPEN EXTEND TRAN-FILE.
WRITE REC.
DISPLAY “File has been Added.”.
CLOSE TRAN-FILE.
STOP RUN.
* A lot more can be done here
Search Example
IDENTIFICATION DIVISION.
PROGRAM-ID. SRCH.
ENVIRONMENT DIVISION.
FILE-CONTROL.
SELECT TRAN-FILE ASSIGN TO "STUDENT.TXT"
ORGANIZATION IS LINE SEQUENTIAL.
DATA DIVISION.
FILE SECTION.
FD TRAN-FILE
LABEL RECORDS ARE STANDARD.
01 TRAN-REC.
03 RNUM
PIC 999.
03 SNAME PIC X(12).
WORKING-STORAGE SECTION.
01 TBL.
03 ENTRIES OCCURS 10 TIMES INDEXED BY IDX.
05 TRNUM
PIC 999.
05 TSNAME PIC X(12).
01 EOF PIC X VALUE "N".
01 VAL PIC 999.
PROCEDURE DIVISION.
BEGIN.
OPEN INPUT TRAN-FILE.
PERFORM VARYING IDX FROM 1 BY 1 UNTIL IDX>7
READ TRAN-FILE
AT END DISPLAY "ERROR"
NOT AT END
MOVE RNO TO RNO1(IDX)
MOVE RNAME TO RNAME1(IDX)
END-READ
END-PERFORM.
CLOSE TRAN-FILE.
DISPLAY "NO:" WITH NO ADVANCING.
ACCEPT VAL.
SEARCH ENTRIES
WHEN RNO1(IDX)=VAL
DISPLAY RNAME1(IDX)
END-SEARCH.
STOP RUN.