CREATE TABLE table_5940 ("Medium" CLOB, "Title" CLOB, "Date" CLOB, "Theatre ,  Studio ,  or Network" CLOB, "Role" CLOB)

What year was there a production created by Adelphi?
SELECT "Date" FROM table_5940 WHERE "Theatre, Studio, or Network" = 'adelphi'
SELECT "Date" FROM "table_5940" WHERE "Theatre, Studio, or Network" = 'adelphi'