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From Apache Wiki <wikidi...@apache.org>
Subject [Db-derby Wiki] Update of "InMemoryBackEndPrimer" by KristianWaagan
Date Mon, 05 Sep 2011 12:48:20 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Db-derby Wiki" for change notification.

The "InMemoryBackEndPrimer" page has been changed by KristianWaagan:

  == How to delete an in-memory database ==
- Proper mechanisms to delete an in-memory database are:
+ The mechanisms to delete an in-memory database are:
   * restart the Java VM,
   * drop database using connection ";drop=true" attribute.
- Also there is inproper way to delete in-memory database, but it shall be considered "unsafe",
may stop working anytime, and will most likely be removed in the next version of Derby. '''Use
it at your own risk'''.
-   * shutdown the database and invoke ''``VFMemoryStorageFactory.purgeDatabase( (new java.io.File(
dbName )).getCanonicalPath() )''.
- '''NOTE''': Depending on the value of ''derby.system.home'', the current working directory
and whether an absolute path is being used, you may have to do ''new java.io.File(System.getProperty("derby.system.home",
"."), dbName)'' (remember to get the canonical path in this case as well).
  == Configuration and tuning ==
  The most important aspect to configure, is the size of the Java heap. When using the in-memory
storage back end, the memory requirement should be similar to the memory requirements of using
the disk-based storage back end plus the size of the user data. The general overhead will
be increased somewhat.

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