user: Question: What year was Portal?
Columns: ['Year', 'Game', 'Genre', 'Platform(s)', 'Developer(s)']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [2006.0, 'Gears of War', 'Tactical Shooter', 'Xbox 360 , Windows', 'Epic Games']
SQL:

assistant: SELECT "Year" FROM "Table" WHERE "Game" = 'Portal';