user: Question: How many dates of vacancy were on 30 October 2010?
Columns: ['Team', 'Outgoing manager', 'Manner of departure', 'Date of vacancy', 'Table', 'Incoming manager', 'Date of appointment']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Tatran Prešov', 'Roman Pivarník', 'Sacked', '22 August 2010', 'Pre-season', 'Ladislav Pecko', '23 August 2010']
SQL:

assistant: SELECT COUNT("Team") FROM "Table" WHERE "Date of vacancy" = '30 October 2010';