Table schema:
CREATE TABLE table_name_30 (year INTEGER, role VARCHAR, title VARCHAR)

Question: What's the average year for the Role of alvin seville simon seville david 'dave' seville, and a Title of the chipmunk adventure?
SQL: SELECT AVG(year) FROM table_name_30 WHERE role = "alvin seville simon seville david 'dave' seville" AND title = "the chipmunk adventure"