user: Question: How many series were directed by Rob Renzetti?
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [8.0, 1.0, '" Peter, Peter, Caviar Eater "', 'Jeff Myers', 'Chris Sheridan', 'September23,1999', '1ACX08']
SQL:

assistant: SELECT COUNT("No. in series") FROM "Table" WHERE "Directed by" = 'Rob Renzetti';