The SET CONTEXT command defines a context as the current context
    and implicitly controls all versioned elements that you define
    while the context is set.

    A context is a nonversioned element. Do not include a version
    number in the context name.

    If the top collection associated with the context is undefined,
    the SET CONTEXT command takes the element named in the next
    command as the top collection for the context. An error occurs
    if the next command is not a DEFINE COLLECTION command.

    The context set remains the current context until you issue
    another SET CONTEXT command, you delete the context, or you end
    the CDO session.

    As an alternative to the SET CONTEXT command, you can define
    the CDD$CONTEXT logical name. Once set, this context becomes the
    current context each time you access the repository. For example:

    $  DEFINE CDD$CONTEXT "cdd$disk:[smith.rep]test_context"