即使所提供的数据不在数据库中（ms访问），我的删除按钮也会一直显示“已成功删除记录”的消息框

I'm working on a library management system, using ms access as the database. My "delete" button can delete a record without a problem but what concerns me is the fact that it prints/displays the JOptionPane messageDialog ("Record successfully deleted ") even when the entry provided is not stored on the database, and worse, even when all the JTextFields are empty. the delete button is named as b11. any help,please? I'm working on a library management system, usi