do not need to re-create DB for each test. Just cleanup the table contents instead.
fix concurrent map writes by adding sync lock
As per golang doc:
Map access is unsafe only when updates are occurring. As long as all goroutines are only reading—looking up elements in the map, including iterating through it using a for range loop—and not changing the map by assigning to elements or doing deletions, it is safe for them to access the map concurrently without synchronization.
concurrent map writesby adding sync lock As per golang doc: