user: Question: what is the tie number that has Portsmouth Home team
Columns: ['Tie no', 'Home team', 'Score', 'Away team', 'Date']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1', 'Darlington', '0–4', 'Wolverhampton Wanderers', '14 January 1998']
SQL:

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