java.sql.SQLException：列索引超出范围，0 < 1

Posted 2023-02-22

【中文标题】java.sql.SQLException：列索引超出范围，0 < 1

【英文标题】：java.sql.SQLException: Column Index out of range, 0 < 1

【发布时间】：2013-12-24 21:13:17

【问题描述】：

我想显示数据库中的所有图像。我已经编写了代码，但是显示错误 java.sql.SQLException: Column Index out of range, 0

| application_name | varchar(45)  | 
| application_id   | varchar(10)  | 
| application_path | varchar(500) | 
| application_icon | blob         | 

我只想显示图像。下面是我的 servlet 代码

图标下载.java

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
            // TODO Auto-generated method stub
            response.setContentType("image/jpeg");
            PrintWriter out=response.getWriter();
            try 
                Connection connection= DBUtil.getConnection();
                PreparedStatement preparedStatement=connection.prepareStatement("select application_icon  from application_master");
                ResultSet resultSet=preparedStatement.executeQuery();
                System.out.println("resultSet"+resultSet);
                out.print("<h1>photo</h1>");
                while (resultSet.next()) 
                    out.print("<img width='200' height='200' src="+resultSet.getBlob(0)+ ">  </img>" );

         catch (ClassNotFoundException e) 
            // TODO Auto-generated catch block
            e.printStackTrace();
         catch (SQLException e) 
            // TODO Auto-generated catch block
            e.printStackTrace();
        

    

【参考方案1】：

列索引应该从 1 开始，而不是 0

http://docs.oracle.com/javase/7/docs/api/java/sql/ResultSet.html#getBlob(int)

参数：columnIndex - 第一列为1，第二列为2，...

应该是

resultSet.getBlob(1) //first column

【参考方案2】：

语句应该是这样的

while (resultSet.next())

resultSet.getBlob(1);

col 索引从 1 到 ...

【参考方案3】：

Blob getBlob(int columnIndex)
             throws SQLException
Retrieves the value of the designated column in the current row of this ResultSet object as a Blob object in the Java programming language.
Parameters:
columnIndex - the first column is 1, the second is 2, ...
Returns:
a Blob object representing the SQL BLOB value in the specified column

您尝试按索引 0 访问列，而枚举从 1 开始