CREATE TABLE table_204_690 (id DECIMAL, "election" DECIMAL, "party name" TEXT, "total votes" DECIMAL, "share of votes" TEXT, "seats" DECIMAL, "share of seats" TEXT, "party leader ( s ) " TEXT, "notes" TEXT)

which party had the most number of seats ?
SELECT "party name" FROM table_204_690 ORDER BY "seats" DESC LIMIT 1
SELECT "party name" FROM "table_204_690" ORDER BY "seats" DESC NULLS LAST LIMIT 1