Question

此问题已在此处得到解答，但发布的解决方案对我不起作用。以下是我的代码：

Statement query = this.conn.createStatement();
            ResultSet resultSet = query.executeQuery("Select COUNT(*) FROM Questions AS total");
            resultSet.next();
            int totalQuestions = resultSet.getInt("total");
            System.out.println(totalQuestions);
            System.exit(1);
            resultSet.close();

它一直在说未找到列总数。我已经尝试过没有“resultSet.next（）”但同样的问题。我也尝试过resultSet.getInt（1），但这也不起作用。

Answer 1

您想要的SQL语法是

Select COUNT(*) AS total FROM Questions

或者，你可以写Select COUNT(*) FROM Questions 并使用resultSet.getInt(1)

Answer 2

变化：

Select COUNT(*) FROM Questions AS total

为：

Select COUNT(*) AS total FROM Questions

Answer 3

你的SQL查询有点不对劲。尝试：

ResultSet resultSet = query.executeQuery("Select COUNT(*) AS total FROM Questions");

Answer 4

像这样更改您的查询，

SQL语法是

Select COUNT(*) AS total FROM Questions

Java：如何从ResultSet Select查询中提取Count

4 个答案: