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DeleteData


Unit:SDL_geodb
Class:TGeoDB
Declaration:procedure DeleteData (DBEntry: longint);

The method DeleteData deletes the database entry DBEntry. DBEntry may take values between 1 and NumEntries. If DBEntry is not within this range, DeleteData is not executed at all.

For performance reasons DeleteData does not delete any associated BLOBs, it simply marks the BLOB as deleted. Thus deleting data may not reduce the size of a database by the expected value. If you want to get rid of any excess data which are no longer needed you should call the GarbageCollection routine.

Hint: Please note that adding or removing data to or from the database changes the database entry numbers. Thus you must not assume that all data are always accessible with the same entry number (i.e. do not use DeleteData in a loop). In order to identify a particular entry you should use the item IDs.

Example: This method is used in the following example program (see http://www.lohninger.com/examples.html for downloading the code): geodata



Last Update: 2012-Oct-20