CREATE TABLE table_204_651 (id DECIMAL, "date" TEXT, "championship" TEXT, "location" TEXT, "category" TEXT, "surface" TEXT, "prev. result" TEXT, "prev. points" DECIMAL, "new points" DECIMAL, "outcome" TEXT)

what was the latest championship to be played in the grand slam category ?
SELECT "championship" FROM table_204_651 WHERE "category" = 'grand slam' ORDER BY "date" DESC LIMIT 1
SELECT "championship" FROM "table_204_651" WHERE "category" = 'grand slam' ORDER BY "date" DESC NULLS LAST LIMIT 1