Question

我的数据库上有一个布尔列，它告诉我用户是否是ADMIN。因此，在删除这些布尔TRUE用户之一之前，我想检查数据库中是否还有一个，如果只有一个，我希望系统不允许删除它。请检查我的代码并提供一些想法，这是到目前为止的代码：

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    boolean aux = false;
    int sum = 0;
    String sqlQuery = "select sum (Admin) from UserInfo";
    try {
            pst = conn.prepareStatement(sqlQuery);
            pst.setInt(1, sum);                   
            pst.execute();
            if (sum >1){
    int q = JOptionPane.showConfirmDialog(null, "Do you really want to delete?", "Confirmation", JOptionPane.YES_NO_OPTION);
    if (q==0) {
    String sql="delete from UserInfo where Name = ?";
    try {
            pst = conn.prepareStatement(sql);
            pst.setString(1, text_name.getText());                   
            pst.execute();
            //JOptionPane.showMessageDialog(null, "Deleted");
    }catch (Exception e) {
        JOptionPane.showMessageDialog(null, e);
    } finally {
        try {
            rs.close();
            pst.close();
        } catch(Exception e) { 
        }
    }
   Update_Table();  
   FieldsCleaner();
 }
            } else {
                JOptionPane.showMessageDialog(null, "Single ADMIN, can't be deleted");
            }

    }catch (Exception e) {
        JOptionPane.showMessageDialog(null, e);
    } finally {
        try {
            rs.close();
            pst.close();
        } catch(Exception e) { 
        }
    }


}

Answer 1

你们给的答案，使我更加努力了。猜猜我已经为此创建了一个非常动态的代码。您可以根据需要使用它。在这里：

private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {                                         
boolean aux = false;
int sum = 0;
try {
    int row = Table_UserInfor.getSelectedRow();
    String Table_click=(Table_UserInfor.getModel().getValueAt(row, 1).toString());
    String sqlQuery ="select * from UserInfo where Name = '"+Table_click+"' ";
    pst =conn.prepareStatement(sqlQuery);
    rs =pst.executeQuery();
    aux=rs.getBoolean("Admin");
    if (rs.next() && aux == true){
        try {
            String sqlCount = "select count(*) cnt from UserInfo where Admin = 1";
            pst =conn.prepareStatement(sqlCount);
            rs =pst.executeQuery();
            sum = rs.getInt("cnt");
            if (rs.next() && sum > 1) {
              int q = JOptionPane.showConfirmDialog(null, "Do you really want to delete?", "Confirmation", JOptionPane.YES_NO_OPTION);
                if (q==0) {
                    String sql="delete from UserInfo where Name = ?";
                    try {
                        pst = conn.prepareStatement(sql);
                        pst.setString(1, text_name.getText());                   
                        pst.execute();
                    }catch (Exception e) {
                        JOptionPane.showMessageDialog(null, e);
                    } finally {
                        try {
                            rs.close();
                            pst.close();
                        } catch(Exception e) { 
                        }
                    }
                    Update_Table();  
                    FieldsCleaner();
                }
                    }else {
                        JOptionPane.showMessageDialog(null, "Single ADMIN, can't be deleted");     
                    }
                    } catch (Exception e) {
                        JOptionPane.showMessageDialog(null, e);            
                    } finally {
                    try {
                        rs.close();
                        pst.close();
                    } catch(Exception e) {
                        JOptionPane.showMessageDialog(null, e);
                    } 
                }
            }
    else if (aux == false){
        int q = JOptionPane.showConfirmDialog(null, "Do you really want to delete?", "Confirmation", JOptionPane.YES_NO_OPTION);
            if (q==0) {
            String sql="delete from UserInfo where Name = ?";
        try {
            pst = conn.prepareStatement(sql);
            pst.setString(1, text_name.getText());                   
            pst.execute();
        }catch (Exception e) {
            JOptionPane.showMessageDialog(null, e);
        } finally {
        try {
            rs.close();
            pst.close();
        } catch(Exception e) { 
        }
    }
        Update_Table();  
        FieldsCleaner();
    }
}
}catch (Exception e) {
    JOptionPane.showMessageDialog(null, e);
} finally {
    try {
        rs.close();
        pst.close();
    } catch(Exception e) { 
    }
}
}

删除前请验证我是否还有一个用户管理员

1 个答案: