progress-4gl TEMP-TABLE Inputting and outputting temp-tables

Example

It's very simple to pass temp-tables in and out of programs, procedures and functions.

This can be handy if you want a procedure to process a bigger number of data than you can easily store in a string or similar. You can pass temp-tables as INPUT, OUTPUT and INPUT-OUTPUT data.

Inputting one temp-table and outputting another:

DEFINE TEMP-TABLE ttRequest NO-UNDO
    FIELD fieldA AS CHARACTER
    FIELD fieldB AS CHARACTER.

/* Define a temp-table with the same fields and indices */
DEFINE TEMP-TABLE ttResponse NO-UNDO LIKE ttRequest.

/* A procedure that simply swap the values of fieldA and fieldB */
PROCEDURE swapFields:
    DEFINE INPUT  PARAMETER TABLE FOR ttRequest.
    DEFINE OUTPUT PARAMETER TABLE FOR ttResponse.

    FOR EACH ttRequest:
        CREATE ttResponse.
        ASSIGN 
            ttResponse.fieldA = ttRequest.fieldB
            ttResponse.fieldB = ttRequest.fieldA.
    END.
END PROCEDURE.

CREATE ttRequest.
ASSIGN ttRequest.fieldA = "A"
       ttRequest.fieldB = "B".

CREATE ttRequest.
ASSIGN ttRequest.fieldA = "B"
       ttRequest.fieldB = "C".

CREATE ttRequest.
ASSIGN ttRequest.fieldA = "C"
       ttRequest.fieldB = "D".

/* Call the procedure */
RUN swapFields ( INPUT  TABLE ttRequest
               , OUTPUT TABLE ttResponse).

FOR EACH ttResponse:
    DISPLAY ttResponse.
END.

Result:

fieldA--------fieldB--------

B             A
C             B
D             C

Input-outputting a temp-table:

DEFINE TEMP-TABLE ttCalculate NO-UNDO
    FIELD num1     AS INTEGER
    FIELD num2     AS INTEGER
    FIELD response AS DECIMAL.

PROCEDURE pythagoras:
    DEFINE INPUT-OUTPUT PARAMETER TABLE FOR ttCalculate.

    FOR EACH ttCalculate:
        ttCalculate.response = SQRT( EXP(num1, 2) + EXP(num2, 2)).
    END.

END PROCEDURE.

CREATE ttCalculate.
ASSIGN ttCalculate.num1 = 3
       ttCalculate.num2 = 4.

CREATE ttCalculate.
ASSIGN ttCalculate.num1 = 6
       ttCalculate.num2 = 8.

CREATE ttCalculate.
ASSIGN ttCalculate.num1 = 12
       ttCalculate.num2 = 16.

/* Call the procedure */
RUN pythagoras ( INPUT-OUTPUT  TABLE ttCalculate ).

FOR EACH ttCalculate:
    DISPLAY ttCalculate.
END.

Result:

----------num1-- ----------num2-- -------response-

         3                4             5.00
         6                8            10.00
        12               16            20.00

Passing to functions

DEFINE TEMP-TABLE ttNumbers NO-UNDO
    FIELD num1     AS INTEGER
    FIELD num2     AS INTEGER
    INDEX index1 num1 num2.

DEFINE VARIABLE iNum AS INTEGER     NO-UNDO.

/* Forward declare the function */
FUNCTION hasAPair RETURNS LOGICAL (INPUT TABLE ttNumbers) FORWARD.

DO iNum = 1 TO 100:
    CREATE ttNumbers.
    ASSIGN ttNumbers.num1 = RANDOM(1,100)
           ttNumbers.num2 = RANDOM(1,100).
END.

MESSAGE hasAPair(INPUT TABLE ttNumbers) VIEW-AS ALERT-BOX.


/* Function to check if two records has the same value in num1 and num2 */
FUNCTION hasAPair RETURNS LOGICAL (INPUT TABLE ttNumbers):

    FIND FIRST ttNumbers WHERE ttNumbers.num1 = ttNumbers.num2 NO-ERROR.
    IF AVAILABLE ttNumbers THEN
        RETURN TRUE.
    ELSE 
        RETURN FALSE.

END FUNCTION.

Passing to program files

You pass temp-tables to and from other .p-programs the same way you pass them to other procedures. The only difference is that both the calling and the called program must have the same temp-table declaration. One easy way is to store the temp-table program in a third file - an include that's used in both programs.

Include file containing temp-table definition: /* ttFile.i */ DEFINE TEMP-TABLE ttFile NO-UNDO FIELD fName AS CHARACTER FORMAT "x(20)" FIELD isADirectory AS LOGICAL.

Program checking all files in a temp-table. Are they directories?

/* checkFiles.p */
{ttFile.i}

DEFINE INPUT-OUTPUT PARAMETER TABLE FOR ttFile.

FOR EACH ttFile:
    FILE-INFO:FILE-NAME = ttFile.fName.

    IF FILE-INFO:FILE-TYPE BEGINS "D" THEN
        ttFile.isADirectory = TRUE.
END.

Main program:

{ttFile.i}

CREATE ttFile.
ASSIGN ttFile.fname = "c:\temp\".

CREATE ttFile.
ASSIGN ttFile.fname = "c:\Windows\".

CREATE ttFile.
ASSIGN ttFile.fname = "c:\Windoose\".

RUN checkFiles.p(INPUT-OUTPUT TABLE ttFile).

FOR EACH ttFile:
    DISPLAY ttFile.
END.

Result:

fName----------------- isADirector

c:\temp\               yes
c:\Windows\            yes
c:\Windoose\           no