user: Question: How many schools with Greyhounds as their nickname?
Columns: ['Institution', 'Location', 'Founded', 'Type', 'Enrollment', 'Nickname', 'Joined', 'Division']
Types: ['text', 'text', 'real', 'text', 'real', 'text', 'real', 'text']
Sample row: ['Adelphi University', 'Garden City, New York', 1896.0, 'Private', 8110.0, 'Panthers', 2009.0, 'Southwest']
SQL:

assistant: SELECT COUNT("Institution") FROM "Table" WHERE "Nickname" = 'Greyhounds';