user: Question: What is the smallest frequency (kHz) that is in the location of Longview?
Columns: ['Frequency (kHz)', 'Call letters', 'Licensed location', 'Type', 'Format']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [600.0, 'KTBB', 'Tyler', 'Primary', 'News / Talk /Sports']
SQL:

assistant: SELECT MIN("Frequency (kHz)") FROM "Table" WHERE "Licensed location" = 'Longview';