RDOHELP72.HLB  —  CREATE_SEGMENT, Examples
    Example 1:

    The following example stores a segmented string:

    START_TRANSACTION READ_WRITE RESERVING
      RESUMES FOR EXCLUSIVE WRITE
    !
    ! Start a stream of segments.  Give the stream a name.
    !
    CREATE_SEGMENTED_STRING RESUME_HANDLE
    !
    ! Store the segments in the field.
    !
    STORE SEG IN RESUME_HANDLE USING
       SEG.RDB$VALUE =
       "This is the first line of an employee's resume."
    END_STORE
    !
    STORE SEG IN RESUME_HANDLE USING
       SEG.RDB$VALUE =
       "This is the second line of an employee's resume."
    END_STORE
    !
    STORE SEG IN RESUME_HANDLE USING
       SEG.RDB$VALUE =
       "This is the third line of an employee's resume."
    END_STORE
    !
    STORE SEG IN RESUME_HANDLE USING
       SEG.RDB$VALUE =
       "This is the fourth line of an employee's resume."
    END_STORE
    !
    ! Store the segmented string field in the relation.
    !
    STORE R IN RESUMES USING
        R.EMPLOYEE_ID = "00164";
        R.RESUME = RESUME_HANDLE
    END_STORE
    !
    END_SEGMENTED_STRING RESUME_HANDLE
    COMMIT

    This sequence of statements demonstrates the steps required to
    store a segmented string:

    o  CREATE_SEGMENTED_STRING starts a "stream" so that you can
       store the segments into the field. The segmented string handle
       gives the stream a name.

    o  Each segmented string STORE statement stores a text string in
       a segment. The context variable SEG relates the values being
       stored to the stream.

    o  The final STORE statement stores the segmented string field
       into the relation, along with the other field, ID_NUMBER. Note
       that this STORE uses the segmented string handle as the value
       expression in the STORE assignment.

    In most cases, this set of statements would be part of a program
    that reads lines from a text file and stores each line in a
    segment of the segmented string field.

    Example 2

    The following program reads a file and loads it into the
    specified employee's RESUMES record in the PERSONNEL database.

    program STORE_RESUME

    !
    ! STORE RESUME
    ! This program reads a file and loads it into the specified
    ! employee's RESUMES record in the PERSONNEL database
    !
            option type = EXPLICIT
            declare long constant TRUE = -1%, FALSE = 0%
            declare                                                 &
                string                                              &
                    employee_id, resume_file, text_line,            &
                    last_name, first_name,                          &
                long                                                &
                    found, line_count

    &RDB&   INVOKE DATABASE FILENAME "DB$:PERSONNEL31"

            print "** Personnel RESUME Load **"
            when error in
                input "Enter EMPLOYEE_ID"; employee_id
            use
                print "Program terminated"
                continue END_PROGRAM
            end when

    &RDB&   START_TRANSACTION READ_WRITE
    &RDB&   FOR E IN EMPLOYEES WITH E.EMPLOYEE_ID = employee_id
    &RDB&       GET
    &RDB&           last_name = E.LAST_NAME;
    &RDB&           first_name = E.FIRST_NAME;
    &RDB&       END_GET
                found = TRUE
    &RDB&   END_FOR

            if not found then
                print "Error - employee " + employee_id + " not found"
                exit program
            else
                !
                ! Display the employees name
                !
                print "Loading RESUME for employee " +              &
                      TRM$(first_name) + ", " + TRM$(last_name)

                !
                ! Read the name of the resume source file
                !
            GET_NAME:
                when error in
                    input "Enter the resume file name"; resume_file
                    open resume_file for input as file #1,          &
                        organization sequential, recordtype ANY
                use
                    if err = 11% then
                        print "Program terminated"
                        continue END_PROGRAM
                    else
                        print "Error - " + RIGHT(ERT$(err),2%)
                        continue GET_NAME
                    end if
                end when

    &RDB&       CREATE_SEGMENTED_STRING RES

                !
                ! Loop and read each line from the resume, and store
                ! it in the segmented string
                !
                line_count = 0%
                while TRUE  ! indefinite loop
                    when error in
                        linput #1, text_line
                    use
                        continue EOF
                    end when
                    text_line = TRM$(text_line)
                    line_count = line_count + 1%
    &RDB&           STORE R IN RES USING
    &RDB&               R.RDB$VALUE = text_line;
    &RDB&               R.RDB$LENGTH = LEN(text_line)
    &RDB&           END_STORE
                next
        EOF:
                close #1
                print line_count; "lines stored in resume."
    &RDB&       STORE RS IN RESUMES USING
    &RDB&           RS.EMPLOYEE_ID = employee_id;
    &RDB&           RS.RESUME = RES
    &RDB&       END_STORE
    &RDB&       END_SEGMENTED_STRING RES
            end if

    &RDB&   commit
    &RDB&   finish

        END_PROGRAM:

    end program
Close Help