String dbName = unescapeIdentifier(ast.getChild(0).getText());
Database database = getDatabase(dbName, true);
ReadEntity dbReadEntity = new ReadEntity(database);
dbReadEntity.noLockNeeded();
inputs.add(dbReadEntity);
SwitchDatabaseDesc switchDatabaseDesc = new SwitchDatabaseDesc(dbName);
rootTasks.add(TaskFactory.get(new DDLWork(getInputs(), getOutputs(),
switchDatabaseDesc), conf));
}