Document Files, Sessions

All MS Visio documents such as diagrams, stencils and templates are handled through index elements in the database.

When a diagram is created, an SCDIAG element is created in the database, and this contains a pseudo attribute (VISF) that provides the file name of the actual file in the file system. File names are composed by <element ID><session no>. This mechanism and naming convention supports the Dabacon session concept and provides a possibility for GLOBAL to manage the files in a multi-location project. These file names are not visible to the user. The user will handle all diagrams through the index elements in the database and will only see the names of the index elements.

This mechanism creates new files each time a Save Work is executed. This means that when users have been working for a certain amount of time, a large quantity of files may exist in the %<PROJECTCODE>DIA% directory, in the same way that a Dabacon database grows as sessions are being added. There is currently no mechanism to automatically delete obsolete versions of the files when a database session merge is executed, however the Diagrams application provides a tool for removing old session files from a project. It could be used manually when KEEP_SESSION_FILES is set to False. For further information, refer to Clean Old Session Files in Chapter Utilities.

At the same time as a diagram file is saved, an SVG format file is optionally created. This is for the purpose of viewing the diagrams in other applications such as the Schematic 3D Integrator without having the need for an MS Visio installation. In the same way as querying the VISF attribute on the SCDIAG element for obtaining the MS Visio diagram file name, the SVG file name can be found by querying the NVIEWF attribute.

On large diagrams, or diagrams that contain detailed imported background drawings, the creation of the SVG file may take some time to execute. This could affect the performance of the Save Work command. For that reason a possibility to control the SVG creation has been introduced.

Whether the SVG file is created or not depends on the General Options > System configuration > SVG setting in Diagrams Options.

• If this setting is False, then the SVG file will only be created if the drawing contains or has contained any items released to 3D.

• If this setting is True, the SVG file will always be created.

When an SVG file is created, there will be a message in the message log indicating this.

Note:
By changing the KEEP_SESSION_FILES default setting to False, only the latest version of the Visio diagram file as well as the SVG file will be kept. Please consider that using this setting will not make it possible to restore a previous session including the corresponding diagram file version.

MS Visio templates and stencils are handled in the same way as the diagrams, using SCTEMP and SCSTEN index elements in the database. One difference however, is that no SVG format files are created when templates and stencils are saved by the application.