在 WHERE 子句中使用 ROW_NUMBER

Question

我正在尝试根据 currentQuestion 整数检索字符串值。但是，我在文档中读到 ROW_NUMBER 不能在 Java Derby 的 WHERE 子句中使用。是否有任何其他功能可以让我根据行号过滤结果？到目前为止，我已经写了这个，虽然我在 getQuestion 字符串上遇到了错误。

public String getQuestion(int currentQuestion) throws SQLException {
        Statement statement = connection.createStatement();

        String getQuestion = ("SELECT QUESTION FROM GAME_TABLE WHERE ROW_NUMBER = ?");
        PreparedStatement preStatement = connection.prepareStatement(getQuestion);
        preStatement.setString(1, Integer.toString(currentQuestion));
        ResultSet resultSet = preStatement.executeQuery();

        System.out.println("Question " + Integer.toString(currentQuestion) + " retrieved.");

        return resultSet.getString(1);
    }

Answer 1

 Statement st = connection.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE);
 String getQuestion = ("SELECT QUESTION FROM GAME_TABLE ");
 ResultSet resultSet = st.executeQuery(getQuestion);
 resultSet.absolute(currentQuestion);// moves the cursor to the row
 return resultSet.getString("Question");

当然这个答案就像得到整个表格后的处理

Answer 2

您可以使用CTE 之类的：

WITH CTE As(
SELECT QUESTION, ROW_NUMBER() OVER (Arguments you want) As RN
FROM GAME_TABLE
)
SELECT *
FROM CTE
WHERE RN = ?;

或者，像这样的子查询：

SELECT T.*
FROM ( SELECT QUESTION, ROW_NUMBER() OVER (Arguments you want) As RN
FROM GAME_TABLE ) As T
WHERE T.RN = ?;