It got started the first time food passed from the table in your hand to their mouth, now how to stop it.
First and a must – no more food from the table. If you breakdown one time, your dog believes “if I beg a little harder they will give in”.
Other tips – have the pooch lie down during dinner or stay in their bed while you eat.
Occasionally placing a leash on your dog and having them lie next to you works. For that dog that knows how to win by pulling on your heart strings – placing this dog in another room behind a closed door is the answer. There will be lots of barking and scratching but in time most dogs understand begging leads to separation.