user: Question: Name the total number of period for Yvon Le Roux
Columns: ['Name', 'Position', 'Period', 'Appearances¹', 'Goals¹', 'Nationality²']
Types: ['text', 'text', 'text', 'real', 'real', 'text']
Sample row: ['Yann Lachuer', 'Midfielder', '1998 – 1999', 25.0, 2.0, 'France']
SQL:

assistant: SELECT COUNT("Period") FROM "Table" WHERE "Name" = 'Yvon Le Roux';