Database: cre_Theme_park
Question: What are the dates when the tourists named Vincent or Vivian visited there?
SQL: select t3.visit_date from tourist_attractions as t1 join visitors as t2 join visits as t3 on t1.tourist_attraction_id  =  t3.tourist_attraction_id and t2.tourist_id  =  t3.tourist_id where t2.tourist_details  =  "vincent" or t2.tourist_details  =  "vivian"