Question

我创建了一个可以改变和检索数据库数据的GUI。但是，即使任务已完成，某些按钮也会抛出SQLException。（例如，它会给我一个错误，但仍然可以正确插入数据库。

这是我的代码：

String sqlUser = e.getActionCommand();
String sql;
PreparedStatement stmt;
try{
    if(sqlUser.equals("Save Record"))
                {
                    ResultSet rs;
                    sql = "INSERT INTO table_name (name, ID, result, date, date2) values (?,?,?,?,?)";
                    stmt = con.prepareStatement(sql);
                    stmt.setString(1, textField.getText());
                    stmt.setInt(2, Integer.parseInt(textField_1.getText()));
                    stmt.setString(3, textField_2.getText());
                    stmt.setDate(4, new java.sql.Date(System.currentTimeMillis()));
                    stmt.setDate(5, new java.sql.Date(System.currentTimeMillis()));
                    rs = stmt.executeQuery();
                    updateUI(rs);
                    con.commit();
                }
    else if(sqlUser.equals("Save Update"))
                {
                    ResultSet rs;
                    sql = "UPDATE table_name SET result = ? , date = ?, date2 = ? WHERE name = ? AND ID = ?";
                    stmt = con.prepareStatement(sql);
                    stmt.setString(4, textField.getText());
                    stmt.setInt(5, Integer.parseInt(textField_1.getText()));
                    stmt.setString(1, textField_2.getText());
                    stmt.setDate(2, new java.sql.Date(System.currentTimeMillis()));
                    stmt.setDate(3, new java.sql.Date(System.currentTimeMillis()));
                    rs = stmt.executeQuery();
                    updateUI(rs);
                    con.commit();
                }
} catch (SQLException err)
{
    JOptionPane.showMessageDialog(null,err.getMessage());
}

updateUI方法如下：

public void updateUI(ResultSet rs)
    {
        try
        {
            String strCDate = dateFormat.format(rs.getDate("date"));
            String strLADate = dateFormat.format(rs.getDate("date2"));

            textField.setText(rs.getString("name"));
            textField_1.setText(Integer.toString(rs.getInt("ID")));
            textField_2.setText(rs.getString("result"));
            lblCalculationDate.setText("Date: " + strCDate);
            lblLastAccessDate.setText("Date2: " + strLADate);
        }
        catch(SQLException err)
        {
            JOptionPane.showMessageDialog(null,err.getMessage());
        }
    }

DateFormat就是这样（不要认为太重要）：

private DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");

Answer 1

删除commit()，因为默认情况下数据库连接是自动提交。
您只能在设置时使用con.setAutoCommit(false); rs = stmt.executeQuery();
插入执行不会返回resultSet，因此请删除String sqlUser = e.getActionCommand(); String sql; PreparedStatement stmt; try{ int id = Integer.parseInt(textField_1.getText()); java.sql.Date date = new java.sql.Date(System.currentTimeMillis()); java.sql.Date date2 = new java.sql.Date(System.currentTimeMillis()); if(sqlUser.equals("Save Record")) { ResultSet rs; sql = "INSERT INTO table_name (name, ID, result, date, date2) values (?,?,?,?,?)"; stmt = con.prepareStatement(sql); stmt.setString(1, textField.getText()); stmt.setInt(2, id); stmt.setString(3, textField_2.getText()); stmt.setDate(4,date ); stmt.setDate(5,date2); // OLD: rs = stmt.executeQuery(); // OLD: updateUI(rs); stmt.executeUpdate(); updateUI(id, textField.getText(),textField_2.getText(),date,date2 ); // OLD: con.commit(); } else if(sqlUser.equals("Save Update")) { ResultSet rs; sql = "UPDATE table_name SET result = ? , date = ?, date2 = ? WHERE name = ? AND ID = ?"; stmt = con.prepareStatement(sql); stmt.setString(4, textField.getText()); stmt.setInt(5, id); stmt.setString(1, textField_2.getText()); stmt.setDate(2, date); stmt.setDate(3, date2); // OLD: rs = stmt.executeQuery(); // OLD: updateUI(rs); stmt.executeUpdate(); updateUI(id, textField.getText(),textField_2.getText(),date,date2 ); // OLD: con.commit(); } } catch (SQLException err) { JOptionPane.showMessageDialog(null,err.getMessage()); } The updateUI method is as follows: public void updateUI(int id, String name, String result, Date date, Date date2) { try { String strCDate = dateFormat.format(date);//rs.getDate("date")); String strLADate = dateFormat.format(date2);//rs.getDate("date2")); textField.setText(name);//rs.getString("name")); textField_1.setText(id+"");//Integer.toString(rs.getInt("ID"))); textField_2.setText(result);//rs.getString("result")); lblCalculationDate.setText("Date: " + strCDate); lblLastAccessDate.setText("Date2: " + strLADate); } catch(SQLException err) { JOptionPane.showMessageDialog(null,err.getMessage()); } }，而是将updateUI方法更改为接受参数的两个日期

全新代码：

Select Mem-Num as 'Member Number'
        ,Scheme Code 'Product Code'
        ,Total
        ,Null
From(
Select Mem-Num,  Total, Scheme Code
from ReportA_table) a

Answer 2

对于插入物和您应该使用

更新

stmt.execute(); rs = stmt.getResultSet();

或

stmt.executeUpdate(); rs = stmt.getResultSet();

此外，由于您未设置con.commit()

，因此您不需要con.setAutoCommit(false)

无关的旁注：作为最佳实践，您应该避免在Java代码中对SQL进行硬编码

错误：ORA-00900无效的SQLStatement但语句仍按预期工作

2 个答案: