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Command history in LINCKS

The commands that are stored in the command history, are the editing commands of the LIBLINCKS interface. Also, two more abstract commands are logged: the composite store and expand; for operations on composite objects. See section 8.4 for a detailed list of commands logged in the command history.

The composite commands will work as a sort of delimiter. For instance, the composite store groups together the detailed store commands in the sequence that stores all newly changed parts of a composite object.

 


:  The integration command history - database

The commands in the command history are linked to the affected objects, and especially the object store command has a link to the object version stored, see figure 11. For this command, it is also useful to have the inverse link, i.e. a link from the object version to the store command, see figure 11. We only store this backlink from the created version to the command history when the command is a store command.

The command history is itself contained in ordinary objects in the database, and thus requires some extra precautions in order to protect it from unauthorized editing.



Martin Sjolin
Thu Jun 15 20:41:59 MET DST 1995