static String buildInsertSql(String table, String[] fields) {
		// TODO:
		StringBuilder sb_field = new StringBuilder();
		StringBuilder sb_value = new StringBuilder();
		for (String field : fields) {
			sb_field.append(field + ", ");
			sb_value.append("?, ");
		}
		sb_field.replace(sb_field.length()-2, sb_field.length(), "");
		sb_value.replace(sb_value.length()-2, sb_value.length(), "");
		return String.format("INSERT INTO %s (%s) VALUES (%s)", table, sb_field, sb_value);
	}