IN SQL: Movie-Rating Query Exercise Movie ( mID, title, year, director ) English: There is a movie with ID number mID, a title, a release year, and a director. Reviewer ( rID, name ) English: The reviewer with ID number rID has a certain name. Rating ( rID, mID, stars, ratingDate ) English: The reviewer rID gave the movie mID a number of stars rating (1-5) on a certain ratingDate.

Q1: Find all years that have a movie that received a rating of 4 or 5, and sort them in increasing order. and now modify the table and add proper index to improve the efficiency of Q1 SELECT query, and use explain syntax to show the efficiency after modification.

Q3: Add a column called "name" in Rating table indicating reviewer's name, with a default value dash '-'.

Q4: Update review's name for rID 201 and 202 in Rating table.