CREATE TABLE table_19754 ("Result" CLOB, "Date" CLOB, "Race" CLOB, "Venue" CLOB, "Group" CLOB, "Distance" CLOB, "Weight  ( kg ) " CLOB, "Jockey" CLOB, "Winner/2nd" CLOB)

How many venues were used on 10 Mar 2007?
SELECT "Venue" FROM table_19754 WHERE "Date" = '10 Mar 2007'
SELECT "Venue" FROM "table_19754" WHERE "Date" = '10 Mar 2007'