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ODB has two binary representations: there is the current format (ODB) which has a "flat" structure, and the older hierarchical format (ODB-1) which is stored in a directory structure instead of a single file. Metview uses the same icon for both ODB formats, hiding the differences between them and providing the users with an interface which is format-transparent. However, please note that wind plotting presently requires different approaches for the ODB and ODB-1 formats, respectively (see the wind plotting exercises (1, 2) for details on the differences).
The ODB Examiner
Right-click on your 'CCMA.obs' ODB Database icon and select examine from the icon menu. This will start the ODB Examiner application that displays the meta-data of the database. By default you should see the Tables tab of the interface showing the ODB table hierarchy. This hierarchy only exists only for the ODB-1 format (so we can see that our 'CCMA.obs' icon represents an ODB-1 database). By clicking on a table name the columns belonging to the selected table are displayed in the right hand side of the interface. There are two more tabs in the interface: the Columns tab showing the list of all the available columns and the SET Variables tab providing the users with the list of pre-defined ODB variables. Explore these tabs and then close the ODB Examiner
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