user: Question: What date was there a Playoff on the margin of victory during the Shirley Englehorn Invitational?
Columns: ['Date', 'Tournament', 'Winning score', 'Margin of victory', 'Runner(s)-up']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Jul 22, 1962', 'Lady Carling Open', '+4 (74-77-75=226)', '3 strokes', 'Mary Mills']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Margin of victory" = 'Playoff' AND "Tournament" = 'Shirley Englehorn Invitational';