Drop a Mistaken Unique Index

The first statement in the editor creates a unique index called idx_courses_room on courses(room). That is a mistake: two courses can share a room in different semesters, and the index now blocks any new course in a room that is already in use. Leave the first statement in place and write the statement that removes the index, so that a second course in room T-100 can be inserted again.

Expected result:

Table courses
✓ id INTEGER PRIMARY KEY
✓ code TEXT NOT NULL
✓ title TEXT NOT NULL
✓ department_id INTEGER NOT NULL
✓ instructor_id INTEGER
✓ credits INTEGER NOT NULL DEFAULT 3
✓ level INTEGER NOT NULL
✓ max_seats INTEGER
✓ room TEXT
✓ semester TEXT
✓ fee REAL
✓ instructor_id REFERENCES instructors(id)
✓ department_id REFERENCES departments(id)
✓ UNIQUE (code)
✓ Insert a second course in room T-100: accepted

Hints2 available

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