CREATE TABLE table_35870 ("Res." CLOB, "Record" CLOB, "Opponent" CLOB, "Method" CLOB, "Event" CLOB, "Round" CLOB)

What round was a loss with a record of 12-3?
SELECT "Round" FROM table_35870 WHERE "Res." = 'loss' AND "Record" = '12-3'
SELECT "Round" FROM "table_35870" WHERE "Record" = '12-3' AND "Res." = 'loss'