When karl ridderbusch is the la roche who is the olivier?
CREATE TABLE "table1_29728787_1" (
  "year" text,
  "conductor" text,
  "opera_house_or_orchestra" text,
  "label" text,
  "countess" text,
  "count" text,
  "flamand" text,
  "olivier" text,
  "la_roche" text,
  "clairon" text
);
SELECT "olivier" FROM "table1_29728787_1" WHERE "la_roche"='Karl Ridderbusch';