user: Question: Which district did Ralph Harvey (R) vacated when he resigned?
Columns: ['District', 'Vacator', 'Reason for change', 'Successor', 'Date successor seated']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Louisiana 7th', 'T. Ashton Thompson (D)', 'Died July 1, 1965', 'Edwin Edwards (D)', 'October 2, 1965']
SQL:

assistant: SELECT "District" FROM "Table" WHERE "Vacator" = 'Ralph Harvey (R)';