The Table Editor Table Field Application
This application edits the Person table in the Personnel database. It is a forms application that allows the user to update a person's values, remove the person, or add new persons. Various table field utilities are provided with the application to demonstrate how they work.
The objects used in this application are shown in the following table:
At the start of the application, a database cursor is opened to load the table field with data from the Person table. Once the table field has been loaded, the user can browse and edit the displayed values. Entries can be added, updated or deleted. When finished, the values are unloaded from the table field, and the user's updates are transferred back into the Person table.
Windows and UNIX:
**
* Program: TABLE-EDIT
*
* Table Editor program. The main program initializes
* the database and displays a form that contains a
* single table field of personnel. It allows the user
* to add, change or delete the rows in the field.
* The program then makes the changes to the
* underlying database table in a multi-statement
* transaction.
**
IDENTIFICATION DIVISION.
PROGRAM-ID. TABLE-EDIT.
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
EXEC SQL INCLUDE SQLCA END-EXEC.
EXEC SQL DECLARE person TABLE
(name char(20),
age smallint,
number integer)
END-EXEC.
EXEC SQL BEGIN DECLARE SECTION END-EXEC.
* Person information
01 PERSONREC.
02 PNAME PIC X(20)
02 P-AGE PIC S99 USAGE COMP.
02 PNUMBER PIC S9(6) USAGE COMP.
01 MAXID PIC S9(6) USAGE COMP.
* Table field entry information
01 RECNUM PIC S9(4) USAGE COMP.
01 LASTROW PIC S9 USAGE COMP.
* Utility buffers
01 MSGBUF PIC X(200).
01 RESPBUF PIC X(20).
01 STATE PIC S9 USAGE COMP.
EXEC SQL END DECLARE SECTION END-EXEC.
* Table field row states:
* Empty or undefined row
01 ST-UNDEF PIC S9 USAGE COMP VALUE 0.
* Appended by user
01 ST-NEW PIC S9 USAGE COMP VALUE 1.
* Loaded by program - not updated
01 ST-UNCHANGED PIC S9 USAGE COMP VALUE 2.
* Loaded by program - since changed
01 ST-CHANGE PIC S9 USAGE COMP VALUE 3.
* Deleted by program
01 ST-DELETE PIC S9 USAGE COMP VALUE 4.
* SQLCA value for no rows
01 NOT-FOUND PIC S9(3) USAGE COMP VALUE 100.
* Update error from database
01 UPDATE-ERROR PIC S9(2) USAGE COMP.
* Transaction aborted
01 XACT-ABORTED PIC S9 USAGE COMP.
PROCEDURE DIVISION.
EXAMPLE SECTION.
XBEGIN.
* Set up error handling for main program
EXEC SQL WHENEVER SQLWARNING CONTINUE END-EXEC.
EXEC SQL WHENEVER NOT FOUND CONTINUE END-EXEC.
EXEC SQL WHENEVER SQLERROR STOP END-EXEC.
* Start Ingres and the Ingres/FORMS system
EXEC SQL CONNECT personnel END-EXEC.
EXEC FRS FORMS END-EXEC.
* Verify that the user can edit the "person" table
EXEC FRS PROMPT NOECHO
('Password for table editor: ', :RESPBUF)
END-EXEC.
IF RESPBUF NOT = "MASTER_OF_ALL" THEN
EXEC FRS MESSAGE 'No permission for task.
Exiting . . .' END-EXEC
EXEC FRS ENDFORMS END-EXEC
EXEC SQL DISCONNECT END-EXEC
STOP RUN.
* We assume no SQL errors can happen during screen updating
EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
EXEC FRS MESSAGE 'Initializing Person Form . . .' END-EXEC.
EXEC FRS FORMINIT personfrm END-EXEC.
* Initialize "persontbl" table field with a data set in FILL
* mode, so that the runtime user can append rows. To keep
* track of events occurring to original rows loaded into the
* table field, hide the unique person number.
EXEC FRS INITTABLE personfrm persontbl FILL
(number = integer)
END-EXEC.
PERFORM LOAD-TABLE THROUGH ENDLOAD-TABLE.
EXEC FRS DISPLAY personfrm UPDATE END-EXEC
EXEC FRS INITIALIZE END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Top' END-EXEC
EXEC FRS BEGIN END-EXEC
* Provide menu items, as well as the system FRS key,
* to scroll to both extremes of the table field.
EXEC FRS SCROLL personfrm persontbl TO 1 END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Bottom' END-EXEC
EXEC FRS BEGIN END-EXEC
EXEC FRS SCROLL personfrm persontbl TO END END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Remove' END-EXEC
EXEC FRS BEGIN END-EXEC
* Remove the person in the row the user's cursor is on.
* If there are no persons, exit operation with message.
* Note that this check cannot really happen, as there
* is always an UNDEFINED row in FILL mode.
EXEC FRS INQUIRE_FRS table personfrm
(:LASTROW = LASTROW(persontbl)) END-EXEC.
IF LASTROW = 0 THEN
EXEC FRS MESSAGE 'Nobody to Remove' END-EXEC
EXEC FRS SLEEP 2 END-EXEC
EXEC FRS RESUME FIELD persontbl END-EXEC.
EXEC FRS DELETEROW personfrm persontbl END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Find' END-EXEC
EXEC FRS BEGIN END-EXEC
* Scroll user to the requested table field entry. Prompt
* the user for a name, and if one is typed in, loop through
* the data set searching for it.
MOVE SPACES TO RESPBUF.
EXEC FRS PROMPT ('Person''s name : ', :RESPBUF)
END-EXEC.
IF RESPBUF = SPACES THEN
EXEC FRS RESUME FIELD persontbl END-EXEC.
EXEC FRS UNLOADTABLE personfrm persontbl
(:PNAME = name,
:RECNUM = _record,
:STATE = _state)
END-EXEC
EXEC FRS BEGIN END-EXEC
* Compare name typed in with names in table, but do
* not compare with deleted rows.
IF PNAME = RESPBUF AND
STATE NOT = ST-DELETE THEN
EXEC FRS SCROLL personfrm persontbl
TO :RECNUM END-EXEC
EXEC FRS RESUME FIELD persontbl END-EXEC.
EXEC FRS END END-EXEC.
* Fell out of loop without finding name. Inform user.
STRING "Person """, RESPBUF,
""" not found in table [HIT RETURN] "
DELIMITED BY SIZE INTO MSGBUF.
EXEC FRS PROMPT NOECHO (:MSGBUF, :RESPBUF) END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Exit' END-EXEC
EXEC FRS BEGIN END-EXEC
EXEC FRS VALIDATE FIELD persontbl END-EXEC.
EXEC FRS BREAKDISPLAY END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS FINALIZE END-EXEC.
* Exit person table editor and unload the table field.
* If any updates, deletions or additions were made,
* duplicate these changes in the source table. If the
* user added new people, assign a unique person id to
* each person before adding the person to the table. To
* do this, increment the previously-saved maximum id
* number with each insert.
* Do all the updates in a transaction
EXEC SQL COMMIT WORK END-EXEC.
* Hard code the error handling in the UNLOADTABLE
* loop, as we want to cleanly exit the loop.
EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
MOVE 0 TO UPDATE-ERROR.
MOVE 0 TO XACT-ABORTED.
EXEC FRS MESSAGE
'Exiting Person Application . . .' END-EXEC.
EXEC FRS UNLOADTABLE personfrm persontbl
(:PNAME = name, :P-AGE = age,
:PNUMBER = number, :STATE = _state)
END-EXEC
EXEC FRS BEGIN END-EXEC
* Row appended by user. Insert into "person" table
* with new unique id.
IF STATE = ST-NEW THEN
ADD 1 TO MAXID
EXEC SQL REPEATED INSERT INTO person
VALUES (:PNAME, :P-AGE, :MAXID) END-EXEC
* Row updated by user. Reflect in table.
ELSE IF STATE = ST-CHANGE THEN
EXEC SQL REPEATED UPDATE person SET
name = :PNAME, age = :P-AGE
WHERE number = :PNUMBER
END-EXEC
* Row deleted by user, so delete from table. Note that
* rows appended by the user at runtime and the
* deleted are not saved and are therefore not unloaded.
ELSE IF STATE = ST-DELETE THEN
EXEC SQL REPEATED DELETE FROM person
WHERE number = :PNUMBER END-EXEC
END-IF.
* Else rows are UNDEFINED or UNCHANGED. No updates.
* Handle error conditions: if an error occurred, abort
* the transaction. If no rows were updated, inform user
* and prompt for continuation.
IF SQLCODE < 0 THEN
EXEC SQL
INQUIRE_SQL(:MSGBUF = ERRORTEXT) END-EXEC
EXEC SQL ROLLBACK WORK END-EXEC
MOVE 1 TO UPDATE-ERROR
MOVE 1 TO XACT-ABORTED
EXEC FRS ENDLOOP END-EXEC
ELSE IF SQLCODE = NOT-FOUND THEN
STRING "Person """, PNAME,
""" not updated. Abort all updates? "
DELIMITED BY SIZE INTO MSGBUF
EXEC FRS PROMPT (:MSGBUF, :RESPBUF) END-EXEC
IF RESPBUF = "Y" OR RESPBUF = "y" THEN
EXEC SQL ROLLBACK WORK END-EXEC
MOVE 1 TO XACT-ABORTED
EXEC FRS ENDLOOP END-EXEC
END-IF
END-IF.
EXEC FRS END END-EXEC.
IF XACT-ABORTED = 0 THEN
EXEC SQL COMMIT END-EXEC.
EXEC FRS ENDFORMS END-EXEC.
EXEC SQL DISCONNECT END-EXEC.
IF UPDATE-ERROR = 1 THEN
DISPLAY
"Your updates were aborted because of error:"
DISPLAY msgbuf.
STOP RUN.
**
* Paragraph: LOAD-TABLE
*
* This paragraph opens a database cursor to load the table
* field with data from the "person" table. The columns
* "name" and "age" will be displayed, and "number" will be
* hidden. It sets the maximum employee number.
**
LOAD-TABLE.
EXEC SQL DECLARE loadtab CURSOR FOR
SELECT name, age, number
FROM person
END-EXEC.
* Set up error handling for loading procedure
EXEC SQL WHENEVER SQLERROR GOTO LOAD-END END-EXEC.
EXEC SQL WHENEVER NOT FOUND GOTO LOAD-END END-EXEC.
EXEC FRS MESSAGE
'Loading Person Information . . .' END-EXEC.
* Fetch the maximum person id number for later use
EXEC SQL SELECT MAX(number) INTO :MAXID
FROM person END-EXEC.
EXEC SQL OPEN loadtab END-EXEC.
PERFORM UNTIL SQLCODE NOT = 0
* Fetch data into record and load table field
EXEC SQL FETCH loadtab INTO :PERSONREC END-EXEC
EXEC FRS LOADTABLE personfrm persontbl
(name = :PNAME, age = :P-AGE, number = :PNUMBER)
END-EXEC
END-PERFORM.
LOAD-END.
EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
EXEC SQL CLOSE loadtab END-EXEC.
ENDLOAD-TABLE.
EXIT
VMS:
IDENTIFICATION DIVISION.
PROGRAM-ID. TABLE-EDIT.
* Table Editor program. The main program initializes the database
* and displays a form that contains a single table field of
* personnel. It allows the user to add, change or delete the rows
* in the field. The program then makes the changes to the
* underlying database table in a multi-statement transaction.
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
EXEC SQL INCLUDE SQLCA END-EXEC.
EXEC SQL DECLARE person TABLE
(name char(20),
age smallint,
number integer)
END-EXEC.
EXEC SQL BEGIN DECLARE SECTION END-EXEC.
* Person information
01 PERSONREC.
02 PNAME PIC X(20).
02 P-AGE PIC S99 USAGE COMP.
02 PNUMBER PIC S9(6) USAGE COMP.
01 MAXID PIC S9(6) USAGE COMP.
* Table field entry information
01 STATE PIC S9 USAGE COMP.
01 RECNUM PIC S9(4) USAGE COMP.
01 LASTROW PIC S9 USAGE COMP.
* Utility buffers
01 MSGBUF PIC X(200).
01 RESPBUF PIC X(20).
EXEC SQL END DECLARE SECTION END-EXEC.
* Table field row states:
* Empty or undefined row
01 ST-UNDEF PIC S9 USAGE COMP VALUE 0.
* Appended by user
01 ST-NEW PIC S9 USAGE COMP VALUE 1.
* Loaded by program - not updated
01 ST-UNCHANGED PIC S9 USAGE COMP VALUE 2.
* Loaded by program - since changed
01 ST-CHANGE PIC S9 USAGE COMP VALUE 3.
* Deleted by program
01 ST-DELETE PIC S9 USAGE COMP VALUE 4.
* SQLCA value for no rows
01 NOT-FOUND PIC S9(3) USAGE COMP VALUE 100.
* Update error from database
01 UPDATE-ERROR PIC S9(2) USAGE COMP.
* Transaction aborted
01 XACT-ABORTED PIC S9 USAGE COMP.
PROCEDURE DIVISION.
BEGIN.
* Set up error handling for main program
EXEC SQL WHENEVER SQLWARNING CONTINUE END-EXEC.
EXEC SQL WHENEVER NOT FOUND CONTINUE END-EXEC.
EXEC SQL WHENEVER SQLERROR STOP END-EXEC.
* Start Ingres and the Ingres/FORMS system
EXEC SQL CONNECT personnel END-EXEC.
EXEC FRS FORMS END-EXEC.
* Verify that the user can edit the "person" table
EXEC FRS PROMPT NOECHO
('Password for table editor: ', :RESPBUF)
END-EXEC.
IF RESPBUF NOT = "MASTER_OF_ALL" THEN
EXEC FRS
MESSAGE 'No permission for task. Exiting . . .'
END-EXEC
EXEC FRS ENDFORMS END-EXEC
EXEC SQL DISCONNECT END-EXEC
STOP RUN.
* We assume no SQL errors can happen during screen updating
EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
EXEC FRS MESSAGE 'Initializing Person Form . . .' END-EXEC.
EXEC FRS FORMINIT personfrm END-EXEC.
* Initialize "persontbl" table field with a data set in FILL
* mode, so that the runtime user can append rows. To keep track
* of events occuring to original rows loaded into the table
* field, hide the unique person number.
EXEC FRS INITTABLE personfrm persontbl FILL
(number = integer)
END-EXEC.
CALL "LOAD-TABLE" GIVING MAXID.
EXEC FRS DISPLAY personfrm UPDATE END-EXEC
EXEC FRS INITIALIZE END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Top' END-EXEC
EXEC FRS BEGIN END-EXEC
* Provide menu items, as well as the system FRS key, to scroll
* to both extremes of the table field.
EXEC FRS SCROLL personfrm persontbl TO 1 END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Bottom' END-EXEC
EXEC FRS BEGIN END-EXEC
EXEC FRS SCROLL personfrm persontbl TO END END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Remove' END-EXEC
EXEC FRS BEGIN END-EXEC
* Remove the person in the row the user's cursor is on. If there
* are no persons, exit operation with message. Note that this
* check cannot really happen, as there is always an UNDEFINED row
* in FILL mode.
EXEC FRS INQUIRE_FRS table personfrm
(:LASTROW = LASTROW(persontbl)) END-EXEC.
IF LASTROW = 0 THEN
EXEC FRS MESSAGE 'Nobody to Remove' END-EXEC
EXEC FRS SLEEP 2 END-EXEC
EXEC FRS RESUME FIELD persontbl END-EXEC.
EXEC FRS DELETEROW personfrm persontbl END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Find' END-EXEC
EXEC FRS BEGIN END-EXEC
* Scroll user to the requested table field entry. Prompt the user
* for a name, and if one is typed in, loop through the data set
* searching for it.
MOVE SPACES TO RESPBUF.
EXEC FRS PROMPT ('Person''s name : ', :RESPBUF)
END-EXEC.
IF RESPBUF = " " THEN
EXEC FRS RESUME FIELD persontbl END-EXEC.
EXEC FRS UNLOADTABLE personfrm persontbl
(:PNAME = name,
:RECNUM = _record,
:STATE = _state)
END-EXEC
EXEC FRS BEGIN END-EXEC
* Compare name typed in with names in table, but do not compare
* with deleted rows.
IF PNAME = RESPBUF AND STATE NOT = ST-DELETE
THEN
EXEC FRS SCROLL personfrm persontbl
TO :RECNUM END-EXEC
EXEC FRS RESUME FIELD persontbl END-EXEC.
EXEC FRS END END-EXEC.
* Fell out of loop without finding name. Inform user.
STRING "Person """ RESPBUF
""" not found in table [HIT RETURN] "
DELIMITED BY SIZE INTO MSGBUF.
EXEC FRS PROMPT NOECHO (:MSGBUF, :RESPBUF) END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS ACTIVATE MENUITEM 'Exit' END-EXEC
EXEC FRS BEGIN END-EXEC
EXEC FRS VALIDATE FIELD persontbl END-EXEC.
EXEC FRS BREAKDISPLAY END-EXEC.
EXEC FRS END END-EXEC
EXEC FRS FINALIZE END-EXEC.
* Exit person table editor and unload the table field. If any
* update, deletions or additions were made, duplicate these
* changes in the source table. If the user added new people,
* assign a unique person id to each person before adding the
* person to the table. To do this, increment the previously-saved
* maximum id number with each insert.
* Do all the updates in a transaction
EXEC SQL COMMIT WORK END-EXEC.
* Hard code the error handling in the UNLOADTABLE loop, as we
* want to cleanly exit the loop.
EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
MOVE 0 TO UPDATE-ERROR.
MOVE 0 TO XACT-ABORTED.
EXEC FRS MESSAGE 'Exiting Person Application . . .'
END-EXEC.
EXEC FRS UNLOADTABLE personfrm persontbl
(:PNAME = name, :P-AGE = age,
:PNUMBER = number, :STATE = _state)
END-EXEC
EXEC FRS BEGIN END-EXEC
* Row appended by user. Insert into "person" table with new
* unique id.
IF STATE = ST-NEW THEN
ADD 1 TO MAXID
EXEC SQL INSERT INTO person (name, age, number)
VALUES (:PNAME, :P-AGE, :MAXID)
END-EXEC
* Row updated by user. Reflect in table.
ELSE IF STATE = ST-CHANGE THEN
EXEC SQL UPDATE person SET
name = :PNAME, age = :P-AGE
WHERE number = :PNUMBER
END-EXEC
* Row deleted by user, so delete from table. Note that rows x
* unique by the user at runtime and then deleted are not saved
* and are therefore not unloaded.
ELSE IF state = ST-DELETE THEN
EXEC SQL DELETE FROM person
WHERE number = :PNUMBER END-EXEC
END-IF.
* Else rows are UNDEFINED or UNCHANGED. No updates.
* Handle error conditions: if an error occurred, abort the
* transaction. If no rows were updated, inform user and prompt
* for continuation.
IF SQLCODE < 0 THEN
EXEC SQL INQUIRE_SQL(:MSGBUF = ERRORTEXT) END-EXEC
EXEC SQL ROLLBACK WORK END-EXEC
MOVE 1 TO UPDATE-ERROR
MOVE 1 TO XACT-ABORTED
EXEC FRS ENDLOOP END-EXEC
ELSE IF SQLCODE = NOT-FOUND THEN
STRING "Person """ PNAME
""" not updated. Abort all updates? "
DELIMITED BY SIZE INTO MSGBUF
EXEC FRS PROMPT (:MSGBUF, :RESPBUF) END-EXEC
IF RESPBUF = "Y" OR RESPBUF = "y" THEN
EXEC SQL ROLLBACK WORK END-EXEC
MOVE 1 TO XACT-ABORTED
EXEC FRS ENDLOOP END-EXEC
END-IF
END-IF.
EXEC FRS END END-EXEC.
IF XACT-ABORTED = 0 THEN
EXEC SQL COMMIT END-EXEC.
EXEC FRS ENDFORMS END-EXEC.
EXEC SQL DISCONNECT END-EXEC.
IF UPDATE-ERROR = 1 THEN
DISPLAY "Your updates were aborted because of error:"
DISPLAY msgbuf.
STOP RUN.
END PROGRAM TABLE-EDIT.
IDENTIFICATION DIVISION.
PROGRAM-ID. LOAD-TABLE.
* This procedure opens a database cursor to load the table field
* with data from the "person" table. The columns "name" and "age"
* will be displayed, and "number" will be hidden. It returns the
* maximum employee number.
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
EXEC SQL INCLUDE SQLCA END-EXEC.
* Person information -- declared to preprocessor in main program
01 PERSONREC.
02 PNAME PIC X(20).
02 P-AGE PIC S99 USAGE COMP.
02 PNUMBER PIC S9(6) USAGE COMP.
01 MAXID PIC S9(6) USAGE COMP.
PROCEDURE DIVISION GIVING MAXID.
BEGIN.
EXEC SQL DECLARE loadtab CURSOR FOR
SELECT name, age, number
FROM person
END-EXEC.
* Set up error handling for loading procedure
EXEC SQL WHENEVER SQLERROR GOTO LOAD-END END-EXEC.
EXEC SQL WHENEVER NOT FOUND GOTO LOAD-END END-EXEC.
EXEC FRS MESSAGE 'Loading Person Information . . .' END-EXEC.
* Fetch the maximum person id number for later use
EXEC SQL SELECT MAX(number) INTO :MAXID FROM person END-EXEC.
EXEC SQL OPEN loadtab END-EXEC.
PERFORM UNTIL SQLCODE NOT = 0
* Fetch data into record and load table field
EXEC SQL FETCH loadtab INTO :PERSONREC END-EXEC
EXEC FRS LOADTABLE personfrm persontbl
(name = :PNAME, age = :P-AGE, number = :PNUMBER)
END-EXEC
END-PERFORM.
LOAD-END.
EXEC SQL WHENEVER SQLERROR CONTINUE END-EXEC.
EXEC SQL CLOSE loadtab END-EXEC.
EXIT PROGRAM.
END PROGRAM LOAD-TABLE.