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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());