6.3.4 AcuODBC READ-ONLY Directive

The AcuODBC READ-ONLY directive allows you to make some fields, or columns, of data read-only, while preserving normal access to other fields or columns. When placed immediately before a data item in an FD, this directive assigns the read-only attribute to the item. The read-only attribute applies only to the next data item with a picture clause and not to group items. Subsequent data items return to normal read-write access.x

Note: This directive applies only to read-write versions of AcuODBC. It is ignored by read-only versions as well as by other products that use the ".xfd" files, for example, alfred.

Syntax

$XFD COMMENT ACUODBC READ-ONLY

*(( XFD COMMENT ACUODBC READ-ONLY ))

In the code creating the "animals" table, the "owner" data item has been designated as read-only. The code is:

       FILE SECTION.
       FD  qa-file.
       01  qa-record.
           03  animal-info.
               05  patient-id                  pic x(5).
               05  atype                       pic x.
               05  ctype redefines atype       pic x.
               05  dtype redefines atype       pic x.
               05  otype redefines atype       pic x.
           03  owner-info.
               05  phone                       pic x(8).
      *(( XFD COMMENT ACUODBC READ-ONLY ))
               05  owner                       pic x(30).
           03  financial.
               05  acct_no.
                   10  year                    pic x(2).
                   10  seq_no                  pic x(4).
               05  last_visit.
                   10  mm                      pic 9(2).
                   10  dd                      pic 9(2).
                   10  yyyy                    pic 9(4).
      $XFD COMMENT ACUODBC HIDDEN
               05  fee                         pic s9(5)v99.
               05  date_paid                   pic 9(8).

In the database table, the "owner" column looks the same as the other column. However, if the data is linked and users attempt to make changes to any of the items in that column, they receive a message telling them that the update on a linked table failed.

If you add this directive to the FD, you should use the xfdcrypt utility included with AcuODBC to encrypt your data dictionaries. Otherwise, users can edit the ".xfd" file to gain access to the read-only fields. See section 6.4, "Encrypting XFD Files", for more information.

Making Entire Tables Read-Only

To make an entire table read-only, you can embed the following statement below the top-level description (containing group item) of the table in the FD. This directive must be placed before the data item that you want mapped to a column in the table.

$XFD COMMENT ACUODBC READ-ONLY TABLE

*(( XFD COMMENT ACUODBC READ-ONLY TABLE ))

For example:

       01  qa_record.
      $XFD COMMENT ACUODBC READ-ONLY TABLE
           03  animal_info.

An exception to the placement of AcuODBC READ-ONLY TABLE directive occurs when the containing group item has another $XFD COMMENT directive associated with it. In such instances, insert the AcuODBC READ-ONLY TABLE directive before the next line (data item) that does not have an $XFD COMMENT associated with it.