CREATE TABLE table_28292 ("Browser" TEXT, "Operating system" TEXT, "Latest stable release" TEXT, "Theora" TEXT, "H.264" TEXT, "VP8  (  WebM  ) " TEXT, "VP9  (  WebM  ) " TEXT)

When theora is 2.3, how much is the h.264?
SELECT "H.264" FROM table_28292 WHERE "Theora" = '2.3'
SELECT "H.264" FROM "table_28292" WHERE "Theora" = '2.3'