user: Question: How many faculty members have 20 years of experience? 
Columns: ['SNO', 'College code', 'Faculty name', 'Designation', 'Qualification', 'Department', 'Experience']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'MQ', 'Dr N. Seshaiah', 'Principal & Professor', 'Ph.D. (Mech)', 'S&H', '20 years']
SQL:

assistant: SELECT COUNT("Designation") FROM "Table" WHERE "Experience" = '20 years';