@Override
	public LinkedList<Sokgraph> query(SqlSpecification specification) throws SQLException {
		// TODO Auto-generated method stub
				
		String cond = specification.toSqlClauses();
		
		String query = "SELECT username,word,graph " +
					   "FROM sokgraph,word_dictionary,account_information "  +
					   "WHERE userid = UID AND " +
					   "wordid = WID AND " +
					   cond +";";
		ResultSet rs = this.dbConnection.execute(query);
		LinkedList<Sokgraph> sokgraphs = this.organizeSokgraphQuery(rs);
		rs.close();
		return sokgraphs;
					   
	}