user: Question: What is the date of Gavril Radomir's Bulgarian victory?
Columns: ['Battle', 'Date', 'Bulgarian Commander', 'Byzantine Commander', 'Result']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Battle of Ongal', '680', 'Asparukh', 'Constantine IV', 'Bulgarian victory']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Result" = 'Bulgarian victory' AND "Bulgarian Commander" = 'Gavril Radomir';