CREATE TABLE table_75051 ("Date" TEXT, "Result" TEXT, "Score" TEXT, "Brazil scorers" TEXT, "Competition" TEXT)

What competition has a result of W on June 30, 1966?
SELECT "Competition" FROM table_75051 WHERE "Result" = 'w' AND "Date" = 'june 30, 1966'
SELECT "Competition" FROM "table_75051" WHERE "Date" = 'june 30, 1966' AND "Result" = 'w'