The difference between Union and Union all is that Union all will not eliminate duplicate rows, instead it just pulls all rows from all tables fitting your query specifics and combines them into a table. A UNION statement effectively does a SELECT DISTINCT on the results set.
Article 370 of the Indian constitution used to give special provision to the region of Jammu and Kashmir. It allows the state to have its own constitution, a separate flag and independence over all matters except foreign affairs, defence and communications. It was adopted in 1947 by then Prime Minister Jawaharlal Nehru.