As a rule, at the beginning of work with the system it is required to select one GDB and open it. To do this you can use an item of the navigation window menu GDB+Open (or the toolbar button 
) In a dialog box “Open GDB” it is possible to select the required GDB file (it has GDB extension).
The pane Open mode has 3 checkboxes enabling to select one of open GDB modes described above or their combination. All modes combinations are possible, however, successful file opening depends on whether the present GDB is opened by some other user and if yes, in which mode.
In the present manual GDB “City” will be widely used (file DEMO\City.GDB). Having selected it, as shown at figure 5-1, one should push the button Open.
Now GDB “City” becomes opened (current). Its name is displayed in the window title bar and the structure pane will contain names of the main GDB component types: Maps, Themes, Tables, Queries, External databases, Layouts, Users and Style library. Besides, if the mode of shared access is selected, then in the pane the component Sessions is displayed. It is not a part of GDB itself and contains a list of all the current user sessions with this GDB.
Every user can open only one GDB at the same time. If the opening operation is performed again the previous current GDB will be closed.
In practice, GDB, when it is stored on a disk, is made of not just one, but nine or ten files in one and the same folder, however, in GDB opening window only one of them is shown. The names of the remaining files differ by adding number “0” or “1” and also by using different extensions (for example, City0.ASS and City1.DAT).
Figure 5-1. Dialog box “Open GDB”
If component type Map and then map “N-city” is opened and “Lands” is selected in the left pane, in the right pane feature types of layer “Lands”, as shown at figure 5-2, will be displayed.
Figure 5-2. The main window: GDB “City” is opened
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