Table: all_creatures_series_info
Columns: dvd_title
no_of_discs
year
no_of_episodes
region_1
region_2
region_4

Question: What is the largest number of episodes for a 1989 season dvd release? 
SQL: SELECT MAX("no_of_episodes") FROM all_creatures_series_info WHERE "year" = '1989'

Question: How many  dvd  titled "series 5" were released having a release date or a non available date in region 2?
SQL: SELECT COUNT("region_2") FROM all_creatures_series_info WHERE "dvd_title" = 'Series 5'