CREATE TABLE table_66619 ("Title" CLOB, "Series" CLOB, "Director" CLOB, "Production Num." CLOB, "Release date" CLOB)

Which series had a release on 1939-07-15 with the 8863 production number?
SELECT "Series" FROM table_66619 WHERE "Release date" = '1939-07-15' AND "Production Num." = '8863'
SELECT "Series" FROM "table_66619" WHERE "Production Num." = '8863' AND "Release date" = '1939-07-15'