Before examining different GDB open modes it is required to consider the main peculiarities of the open mode which will be offered by default after the system installation. For convenience this mode will be called standard open mode below and in description of other modes their differences from the standard one will be indicated.
It should be emphasized that the name “standard mode” does not mean some advantage of this mode over others, it is more likely only to reflect high frequency of use of this mode compared with others.
In the standard mode GDB will be opened for exclusive access, that is, attempts of other users to open the same GDB before it is closed by the present user will be rejected (it should be noted that GDB can be closed when calling GDB+Close command, when opening another GDB and also during ObjectLand work termination).
GDB will be opened for reading and writing. In other words, the user will have a possibility to browse GDB contents and also make changes of the data and database structure (provided that making changes is not prohibited for a particular user at the level of permissions differentiation).
Changes made by the user to GDB will be immediately recorded into GDB files. If in the course of some operation changing GDB emergency system termination occurs (for example, electricity supply switch off, hardware failure or computer restart), to provide data integrity the uncompleted operation will be rolled back next time the GDB is opened.
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