Joanna Kerns กำกับโดย Joanna Kerns มีกี่ซีซั่น? ไม่จำเป็นต้องใช้ตารางทั้งหมด
What was the number of seasons that was directed by Joanna Kerns?It is not neccessary to use all the tables.
 table_17356106_1:  (season__number [ VARCHAR ] directed_by [ VARCHAR) ]
SELECT COUNT(season__number) FROM table_17356106_1 WHERE directed_by = "Joanna Kerns"