Data in GDB files is located so that on the one hand make it possible to perform such operations as searching, adding, changing or removing data quickly and on the other hand to effectively use the disk space. However, mass data changes lead to fragmentation in GDB files, that is, the appearance of unused file spaces. The consequence is excessive use of disk space and slowdown of work with the present GDB. The degree of effectiveness of using disk space can be evaluated by performing the command GDB+Properties and selecting the tab General in the opened property sheet.
Reorganization operation optimizes arrangement of data in the files restores work effectiveness. The decision about performing reorganization operation should be taken on the basis of analysis of information about GDB given by Properties command.
During GDB reorganization the user can also change sizes of GDB file pages (see chapter 7 “GDB properties”, subsection “Page “Parameters”” and chapter 8 “System parameters setting”, subsection “Page “GDB creating””).
To perform reorganization the menu command GDB+Reorganize should be used. The system opens a dialog box “Select GDB for reorganization”. After selecting GDB for reorganization in this box and pushing the button Open the system opens a dialog box “GDB reorganization” shown at figure 6-4.
Figure 6-4. Dialog box “GDB reorganization”
If the user pushes the button Change pages sizes a dialog box is extended and looks like it is shown at figure 6-5
Figure 6-5. Dialog box “GDB reorganization” with page sizes
The user can change page size shown in the box. After pushing the button Reorganization the system performs the corresponding operations.
Data reorganization is a laborious operation which can take considerable time if GDB size is big. On completing the operation the system informs: “Reorganization of GDB <GDB name> completed successfully”. It is impossible to reorganize GDB which is current at the present moment. First all the users should close this GDB.
If there is differentiation of user permissions assigned for this particular GDB then only the administrator can reorganize it. Before performing the operation the system asks to enter name and password of the administrator.
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