user: Question: What is the tie number when the home team is Port Vale?
Columns: ['Tie no', 'Home team', 'Score', 'Away team', 'Date']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1', 'Chester', '1–0', 'Luton Town', '29 January 1977']
SQL:

assistant: SELECT "Tie no" FROM "Table" WHERE "Home team" = 'Port Vale';