Library Version 18.1.40

Administrative Methods
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## Administrative Methods

Both the `Environment` and `Database` classes provide methods that are useful for manipulating databases. These methods are:

- `Database.getDatabaseName()`

  Returns the database's name.

      String dbName = myDatabase.getDatabaseName();

- `Database.rename()`

  Renames the specified database. If no value is given for the `database` parameter, then the entire file referenced by this method is renamed.

  Never rename a database that has handles opened for it. Never rename a file that contains databases with opened handles.

      import java.io.FileNotFoundException;
      ...
      myDatabase.close();
      try {
          myDatabase.rename("mydb.db",     // Database file to rename
                            null,          // Database to rename. Not used so
                                           // the entire file is renamed.
                            "newdb.db",    // New name to use.
                            null);         // DatabaseConfig object.
                                           // None provided.
      } catch (FileNotFoundException fnfe) {
          // Exception handling goes here
      }

- `Environment.truncateDatabase()`

  Deletes every record in the database and optionally returns the number of records that were deleted. Note that it is much less expensive to truncate a database without counting the number of records deleted than it is to truncate and count.

      int numDiscarded =
          myEnv.truncate(null,                          // txn handle
                         myDatabase.getDatabaseName(),  // database name
                         true);                         // If true, then the
                                                        // number of records
                                                        // deleted are counted.
      System.out.println("Discarded " + numDiscarded +
                         " records from database " +
                         myDatabase.getDatabaseName());

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