What are the names of parties that have both delegates on "Appropriations" committee and
SELECT T2.Party FROM election AS T1 JOIN party AS T2 ON T1.Party  =  T2.Party_ID WHERE T1.Committee  =  "Appropriations" INTERSECT SELECT T2.Party FROM election AS T1 JOIN party AS T2 ON T1.Party  =  T2.Party_ID WHERE T1.Committee  =  "Economic Matters"
parties that have delegates on both 'Appropriations' committee and 'Economic Matters' committee are found by intersecting the sets of parties from each committee; JOIN is used to connect party information between 'election' and 'party' tables based on party ID; INTERSECT is used to find common entries between two SELECT queries;