Table: superman_appearances
Columns: character_s
first_appearance
cover_date
publisher
estimated_value

Question:  what's the first appearance where character(s) is iron man
SQL: SELECT "first_appearance" FROM superman_appearances WHERE "character_s" = 'Iron Man'

Question: what is the total number of publisher where cover date is may 1939
SQL: SELECT COUNT("publisher") FROM superman_appearances WHERE "cover_date" = 'May 1939'

Question: what is the total number of publisher where first appearance is daredevil #1
SQL: SELECT COUNT("publisher") FROM superman_appearances WHERE "first_appearance" = 'Daredevil #1'

Question:  what's the cover date where character(s) is sandman (wesley dodds)
SQL: SELECT "cover_date" FROM superman_appearances WHERE "character_s" = 'Sandman (Wesley Dodds)'

Question:  what's the cover date where character(s) is x-men ; magneto
SQL: SELECT "cover_date" FROM superman_appearances WHERE "character_s" = 'X-Men ; Magneto'

Question:  what's the estimated value where cover date is august 1962
SQL: SELECT "estimated_value" FROM superman_appearances WHERE "cover_date" = 'August 1962'