What is the result against Errol Zimmerman on 2007-04-07?
CREATE TABLE "kickboxing_record" (
  "date" text,
  "result" text,
  "opponent" text,
  "location" text,
  "method" text
);
SELECT "result" FROM "kickboxing_record" WHERE "opponent"='errol zimmerman' AND "date"='2007-04-07';