CREATE TABLE table_30027 ("Year" FLOAT, "Location" TEXT, "Distance  ( miles ) " FLOAT, "Rider Names" TEXT, "Horse Name" TEXT, "Best-Conditioned Horse" TEXT)

How many different riders are there that won riding Omr Tsunami?
SELECT COUNT("Rider Names") FROM table_30027 WHERE "Horse Name" = 'OMR Tsunami'
SELECT COUNT("Rider Names") FROM "table_30027" WHERE "Horse Name" = 'OMR Tsunami'