Auditing

Rationale

Auditing guarantees that all the operations on the database:

  • Are performed in a non-destructive manner – This means that it is always possible for a DBA to revert changes that have been made.
  • Every change has indication of when that change was made and who did that change (if the user is known by the system).

This means that a DBA can always revert changes, and see who did what and when.

This feature is only available when using the relational persistence layer.

Usage

For auditing to work, Form Runner needs to know who is presently using the application. There are two ways in which Form Runner can determine the current username:

  • Container - It can ask the container (i.e. servlet container or application server). This is typically useful when users log into the application using basic or form-based authentication.
  • Header - It can get the username from an HTTP header. This is typically useful when you are using some type of front-end which "knows" who the user is and thus can pass this information to Form Runner through a header.

For more details on this configuration, see Access Control.

Implementation for relational databases

When you use the Oracle or MySQL persistence layer:

  • Every table has the following 4 columns:
    • created tells you when given the data (e.g. attachment to a form for the orbeon_form_data_attach).
    • last_modified tells you when the data was last changed.
    • username tells you who did that change.
    • deleted tells you if the data is marked as deleted, and hence invisible to users.
  • Once a row is added to a column, it is never updated or deleted. Only new rows are added.
  • When data is first added to a table, created and last_modified have the same value. Then, when this data is modified, another row is added: created is copied over and last_modified is set to the current time stamp.
  • When data is deleted by users, a new row is added. This row is a copy of the latest row for the data that is being deleted, except for last_modified which is set to the current time stamp and deleted which is set to Y.

See also