CREATE TABLE table_21002034_7 (_number INT, air_date_netherlands_yyyy_mm_dd VARCHAR)

Name the most number for air date 2009/12/29
SELECT MAX(_number) FROM table_21002034_7 WHERE air_date_netherlands_yyyy_mm_dd = "2009/12/29"
SELECT MAX("_number") FROM "table_21002034_7" WHERE "2009/12/29" = "air_date_netherlands_yyyy_mm_dd"