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The Professor–Student Mixed Form Application
This application lets the user browse and update information about graduate students who report to a specific professor. The program is structured in a master/detail fashion, with the professor being the master entry, and the students the detail entries. The application uses two forms—one to contain general professor information and another for detailed student information.
The objects used in this application are shown in the following table:
Object
Description
personnel
The program's database environment.
professor
A database table with two columns:
   pname (char(25))
   pdept (char(10)).
See its declare table statement in the program for a full description.
student
A database table with seven columns:
   sname (char(25))
   sage (integer1)
   sbdate (char(25))
   sgpa (float4)
   dofmp (integer)
   scomment (varchar(200))
   sadvisor (char(25)).
See its declare table statement for a full description. The sadvisor column is the join field with the pname column in the Professor table.
masterfrm
The main form has the pname and pdept fields, which correspond to the information in the Professor table, and the studenttbl table field. The pdept field is display‑only.
studenttbl
A table field in "masterfrm" with two columns, sname and sage. When initialized, it also has five hidden columns corresponding to information in the Student table.
studentfrm
The detail form, with seven fields, which correspond to information in the Student table. Only the sgpa, scomment, and sadvisor fields are updatable. All other fields are display‑only.
grad
A structure whose members correspond in name and type to the columns of the Student database table, the studentfrm form and the studenttbl table field.
The program uses the masterfrm as the general‑level master entry, in which data can only be retrieved and browsed, and the studentfrm as the detailed screen, in which specific student information can be updated.
The runtime user enters a name in the pname field and then selects the Students menu operation. The operation fills the studenttbl table field with detailed information of the students reporting to the named professor. This is done by the database cursor "studentcsr" in the LOAD‑STUDENTS paragraph. The program assumes that each professor is associated with exactly one department. The user may then browse the table field (in read mode), which displays only the names and ages of the students. More information about a specific student may be requested by selecting the Zoom menu operation. This operation displays the form studentfrm (in update mode). The fields of studentfrm are filled with values stored in the hidden columns of studenttbl. The user may make changes to three fields (sgpa, scomment, and sadvisor). If validated, these changes will be written back to the database table (based on the unique student id), and to the table field's data set. This process can be repeated for different professor names.
       IDENTIFICATION DIVISION.
       PROGRAM-ID.  STUDENT-ADMINISTRATOR.
       ENVIRONMENT DIVISION.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       EXEC SQL INCLUDE SQLCA END-EXEC.
*      Graduate student table
       EXEC SQL DECLARE student TABLE
            (sname      char(25),
             sage       integer1,
             sbdate     char(25),
             sgpa       float4,
             sidno      integer,
             scomment   varchar(200),
             sadvisor   char(25))
             END-EXEC.
*      Professor table
       EXEC SQL DECLARE professor TABLE
           (pname      char(25),
            pdept      char(10))
           END-EXEC.
       EXEC SQL BEGIN DECLARE SECTION END-EXEC.
*      Global grad student record maps to database table
       01 GRAD.
           02 SNAME        PIC X(25).
           02 SAGE         PIC S9(4) USAGE COMP.
           02 SBDATE       PIC X(25).
           02 SGPA         PIC S9(10)V9(8) USAGE COMP.
           02 SIDNO        PIC S9(9) USAGE COMP.
           02 SCOMMENT     PIC X(200).
           02 SADVISOR     PIC X(25).
*      Professor info maps to database table
       01 PROF.
           02 PNAME      PIC X(25).
           02 PDEPT      PIC X(10).
*      Row number of last row in student table field
       01 LASTROW        PIC S9(9) USAGE COMP.
*      Is user on a table field?
       01 ISTABLE          PIC S9 USAGE COMP.
*      Were changes made to data in "studentfrm"?
       01 CHANGED-DATA     PIC S9 USAGE COMP.
       Did user enter a valid advisor name?
       01 VALID-ADVISOR    PIC S9 USAGE COMP.
*      "Studentfrm" loaded?
       01 LOADFORM         PIC S9 USAGE COMP VALUE IS 0.
*      Local utility buffers
       01 MSGBUF           PIC X(200).
       01 RESPBUF          PIC X.
       01 OLD-ADVISOR      PIC X(25).
*      Compiled forms are not yet accepted as
*      EXTERNAL due to restrictions noted in the chapter
*      that describes how to link the RTS with compiled
*      forms.  Consequently, declarations of external
*      form objects and the corresponding ADDFORM
*      statement have been commented out and replaced by
*      a CALL "add_formname" statement.
*      01    masterfrm  PIC S9(9) USAGE COMP-5 IS EXTERNAL.
*      01    studentfrm PIC S9(9) USAGE COMP-5 IS EXTERNAL.
       EXEC SQL END DECLARE SECTION END-EXEC.
**
*      Procedure Division: STUDENT-ADMINISTRATOR
*
*      Start up program, Ingres and the FORMS system and
*      call Master driver.
**
       PROCEDURE DIVISION.
       EXAMPLE SECTION.
       XBEGIN.
       EXEC FRS FORMS END-EXEC.
       EXEC SQL WHENEVER SQLERROR STOP END-EXEC.
       EXEC FRS MESSAGE 'Initializing Student
                          Administrator .  .' END-EXEC.
       EXEC SQL CONNECT personnel END-EXEC.
       PERFORM MASTER THRU END-MASTER.
       EXEC FRS CLEAR SCREEN END-EXEC.
       EXEC FRS ENDFORMS END-EXEC.
       EXEC SQL DISCONNECT END-EXEC.
       STOP RUN.
**
*      Paragraph: MASTER
*
*      Drive the application, by running "masterfrm", and
*      allowing the user to "zoom" into a selected student.
**
       MASTER.
*      EXEC FRS ADDFORM :masterfrm END-EXEC.
       CALL "add_masterfrm".

*      Initialize "studenttbl" with a data set in READ mode.
*      Declare hidden columns for all the extra fields that the
*      program will display when more information is requested
*      about a student.  Columns "sname" and "sage" are displayed,
*      all other columns are hidden, the student information 
*      form.
       EXEC FRS INITTABLE masterfrm studenttbl READ
               (sbdate   = char(25),
                sgpa     = float4,
                sidno    = integer,
                scomment = char(200),
                sadvisor = char(20))
                END-EXEC.
       EXEC FRS DISPLAY masterfrm UPDATE END-EXEC
       EXEC FRS INITIALIZE END-EXEC
       EXEC FRS BEGIN END-EXEC
              EXEC FRS MESSAGE 
                         'Enter an Advisor name . . .' END-EXEC.
              EXEC FRS SLEEP 2 END-EXEC.
       EXEC FRS END END-EXEC
       EXEC FRS ACTIVATE MENUITEM 
              'Students', FIELD 'pname' END-EXEC
       EXEC FRS BEGIN END-EXEC
*            Load the students of the specified professor
             EXEC FRS GETFORM (:PNAME = pname) END-EXEC
*            If no professor name is given, resume
             IF PNAME = SPACES THEN
                        EXEC FRS RESUME FIELD pname END-EXEC.
*            Verify the professor exists.  Local error handling
*            just prints the message, and continues.  We assume
*            that each professor has exactly one department.
             EXEC SQL WHENEVER SQLERROR CALL SQLPRINT END-EXEC.
             EXEC SQL WHENEVER NOT FOUND CONTINUE END-EXEC.
             MOVE SPACES TO PDEPT.
             EXEC SQL SELECT pdept
                      INTO :PDEPT
                      FROM professor
                      WHERE pname = :PNAME
                      END-EXEC.
       IF PDEPT = SPACES THEN
                      STRING "No professor with name """, PNAME,
                            """ [RETURN]" DELIMITED BY SIZE
                            INTO MSGBUF
                       EXEC FRS PROMPT NOECHO (:MSGBUF, :RESPBUF)
                             END-EXEC
                       EXEC FRS CLEAR FIELD ALL END-EXEC
                       EXEC FRS RESUME FIELD pname END-EXEC.
*              Fill the department field and load students
               EXEC FRS PUTFORM (pdept = :PDEPT) END-EXEC.
*              Refresh for query
               EXEC FRS REDISPLAY END-EXEC.
               PERFORM LOAD-STUDENTS THRU END-LOAD.
               EXEC FRS RESUME FIELD studenttbl END-EXEC.
       EXEC FRS END END-EXEC
       EXEC FRS ACTIVATE MENUITEM 'Zoom' END-EXEC
       EXEC FRS BEGIN END-EXEC
*           Confirm that user is on "studenttbl", and that the
*           table field is not empty.  Collect data from the row
*           and zoom for browsing and updating.
            EXEC FRS INQUIRE_FRS field
                            masterfrm (:ISTABLE = table)
                  END-EXEC.
            IF ISTABLE = 0 THEN
                  EXEC FRS PROMPT NOECHO
                         ('Select from the student 
                                        table [RETURN]',
                          :RESPBUF) END-EXEC
            EXEC FRS RESUME FIELD studenttbl END-EXEC.
            EXEC FRS INQUIRE_FRS table masterfrm
                     (:LASTROW = lastrow) END-EXEC.
            IF LASTROW = 0 THEN
                    EXEC FRS PROMPT NOECHO
                             ('There are no students [RETURN]',
                               :RESPBUF) END-EXEC
                    EXEC FRS RESUME FIELD pname END-EXEC.
*           Collect all data on student into global record
            EXEC FRS GETROW masterfrm studenttbl
                          (:SNAME   = sname,
                           :SAGE    = sage,
                           :SBDATE  = sbdate,
                           :SGPA    = sgpa,
                           :SIDNO   = sidno,
                           :SCOMMENT = scomment,
                           :SADVISOR = sadvisor)
                           END-EXEC.
*          Display "studentfrm", and if any changes were made
*          make the updates to the local table field row.  Only
*          updates to the columns corresponding to writable fields
*          in "studentfrm".  If the student changed advisors, then
*          delete this row from the display.
           MOVE SADVISOR TO OLD-ADVISOR.
           PERFORM STUDENT-INFO-CHANGED THRU END-STUDENT.
           IF CHANGED-DATA = 1 THEN
                IF OLD-ADVISOR NOT = SADVISOR THEN
                           EXEC FRS DELETEROW masterfrm studenttbl
                                END-EXEC
                ELSE
                           EXEC FRS PUTROW masterfrm studenttbl
                                 (sgpa = :SGPA,
                                  scomment = :SCOMMENT,
                                  sadvisor = :SADVISOR)
                                 END-EXEC
                END-IF
       END-IF.
       EXEC FRS END END-EXEC
       EXEC FRS ACTIVATE MENUITEM 'Exit' END-EXEC
       EXEC FRS BEGIN END-EXEC
              EXEC FRS BREAKDISPLAY END-EXEC.
       EXEC FRS END END-EXEC
       EXEC FRS FINALIZE END-EXEC
       END-MASTER.
             EXIT.
**
*      Paragraph: LOAD-STUDENTS
*
*      For the current professor name, this paragraph loads into
*      the "studenttbl" table field all the students whose
*      advisor is the professor with that name.
**
       LOAD-STUDENTS.
       EXEC SQL DECLARE studentcsr CURSOR FOR
                SELECT sname, sage, sbdate, sgpa,
                       sidno, scomment, sadvisor
                FROM student
                WHERE sadvisor = :PNAME
                END-EXEC.
*      Clear previous contents of table field.  Load the table
*      field from the database table based on the advisor name.
*      Columns "sname" and "sage" will be displayed, and all
*      others will be hidden.
       EXEC FRS MESSAGE 'Retrieving Student Information . . .'
                 END-EXEC.
       EXEC FRS CLEAR FIELD studenttbl END-EXEC.
       EXEC SQL WHENEVER SQLERROR GOTO END-LOAD END-EXEC.
       EXEC SQL WHENEVER NOT FOUND GOTO END-LOAD END-EXEC.
       EXEC SQL OPEN studentcsr END-EXEC.
*      Before we start the loop, we know that the OPEN was
*      successful and that NOT FOUND was not set.
       PERFORM UNTIL SQLCODE NOT = 0
              EXEC SQL FETCH studentcsr INTO :GRAD END-EXEC
              EXEC FRS LOADTABLE masterfrm studenttbl
                           (sname    = :SNAME,
                            sage     = :SAGE,
                            sbdate   = :SBDATE,
                            sgpa     = :SGPA,
                            sidno    = :SIDNO,
                            scomment = :SCOMMENT,
                            sadvisor = :SADVISOR)
                            END-EXEC
       END-PERFORM.
       END-LOAD.
*      Clean up on an error, and close cursors
       EXEC SQL WHENEVER NOT FOUND CONTINUE END-EXEC.
       EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
       EXEC SQL CLOSE studentcsr END-EXEC.
**
*     Paragraph: STUDENT-INFO-CHANGED
*
*     Allow the user to zoom into the details of a selected
*     student.  Some of the data can be updated by the user.
*     If any updates were made, then reflect these back into
*     the database table.  The paragraph records whether or not
*     changes were made via the CHANGED-DATA variable.
**
       STUDENT-INFO-CHANGED.
*      Control ADDFORM to only initialize once
       IF LOADFORM = 0 THEN
           EXEC FRS MESSAGE 'Loading Student form . . .' END-EXEC
           EXEC FRS ADDFORM :studentfrm END-EXEC
           CALL "add_studentfrm"
           MOVE 1 TO LOADFORM.
*      Local error handle just prints error and continues
       EXEC SQL WHENEVER SQLERROR CALL SQLPRINT END-EXEC.
       EXEC SQL WHENEVER NOT FOUND CONTINUE END-EXEC.
       EXEC FRS DISPLAY studentfrm FILL END-EXEC
       EXEC FRS INITIALIZE
               (sname    = :SNAME,
                sage     = :SAGE,
                sbdate   = :SBDATE,
                sgpa     = :SGPA,
                sidno    = :SIDNO,
                scomment = :SCOMMENT,
                sadvisor = :SADVISOR)
                END-EXEC
        EXEC FRS ACTIVATE MENUITEM 'Write' END-EXEC
        EXEC FRS BEGIN END-EXEC
*            If changes were made, update the database table.
*            Only bother with the fields that are not read-only.
             EXEC FRS INQUIRE_FRS form (:CHANGED-DATA = change)
                    END-EXEC.
             IF CHANGED-DATA = 0 THEN
                    EXEC FRS BREAKDISPLAY END-EXEC.
             EXEC FRS VALIDATE END-EXEC.
             EXEC FRS MESSAGE
                  'Writing changes to database. . .' END-EXEC.
             EXEC FRS GETFORM
                     (:SGPA = sgpa,
                      :SCOMMENT = scomment,
                      :SADVISOR = sadvisor)
                     END-EXEC.
*            Enforce integrity of professor name.
             MOVE 0 TO VALID-ADVISOR.
             EXEC SQL SELECT 1 INTO :VALID-ADVISOR
                      FROM professor
                      WHERE pname = :SADVISOR
                      END-EXEC.
             IF VALID-ADVISOR = 0 THEN
                    EXEC FRS MESSAGE
                        'Not a valid advisor name'
                        END-EXEC
                    EXEC FRS SLEEP 2 END-EXEC
                    EXEC FRS RESUME FIELD sadvisor END-EXEC
             ELSE
                    EXEC SQL UPDATE student SET
                          sgpa     = :SGPA,
                          scomment = :SCOMMENT,
                          sadvisor = :SADVISOR
                          WHERE sidno = :SIDNO
                          END-EXEC
                    EXEC FRS BREAKDISPLAY END-EXEC
             END-IF.
        EXEC FRS END END-EXEC
        EXEC FRS ACTIVATE MENUITEM 'Quit' END-EXEC
        EXEC FRS BEGIN END-EXEC
*          Quit without submitting changes
           MOVE 0 TO CHANGED-DATA.
           EXEC FRS BREAKDISPLAY END-EXEC.
       EXEC FRS END END-EXEC
       EXEC FRS FINALIZE END-EXEC
       END-STUDENT.
             EXIT. 
Last modified date: 11/09/2022