user: Question: How long was Volume:Issue 12:4-6 at the top?
Columns: ['Volume:Issue', 'Issue Date(s)', 'Weeks on Top', 'Song', 'Artist']
Types: ['text', 'text', 'real', 'text', 'text']
Sample row: ['10:16-19', '16 December 1968 - 6 January', 4.0, '" Wichita Lineman "', 'Glen Campbell']
SQL:

assistant: SELECT "Weeks on Top" FROM "Table" WHERE "Volume:Issue" = '12:4-6';