user: Question: Which surface had a partner of Sandrine Testud on November 14, 1999?
Columns: ['Outcome', 'Date', 'Tournament', 'Surface', 'Partner', 'Opponents in the final', 'Score']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Winners', 'September 26, 1993', 'Tokyo , Japan', 'Hard', 'Lisa Raymond', 'Amanda Coetzer Linda Wild', '6–4, 6–1']
SQL:

assistant: SELECT "Surface" FROM "Table" WHERE "Partner" = 'Sandrine Testud' AND "Date" = 'November 14, 1999';