CREATE TABLE table_46052 ("Team" TEXT, "Tries for" TEXT, "Tries against" TEXT, "Try diff" TEXT, "Points for" TEXT, "Points against" TEXT, "Points diff" TEXT)

What is points diff when points against is 123?
SELECT "Points diff" FROM table_46052 WHERE "Points against" = '123'
SELECT "Points diff" FROM "table_46052" WHERE "Points against" = '123'