update picture in the database using php codeigniter

get the code from the given link

today we will see how to update picture in data
1. create a page in views folder for updation
copy the add page and rename it.
2. give the id for update in the link at the view page
3. create a function update in controller
4. first time when we click on update the form should be
displayed so $data will be empty and when we submit
the form $data will not be empty any more.
5. we create a func in model
6. now we make changes in the update page
7. three lines are used for picture updation.
remaining will be in the nxt video.