Table: us_womens_open_results
Columns: date
tournament
winning_score
margin_of_victory
runner_s_up

Question: What was the date of the match with a winning score of –7 (67-72-69-69=277)?
SQL: SELECT "date" FROM us_womens_open_results WHERE "winning_score" = '–7 (67-72-69-69=277)'