What is the bore of the boat howitzers with a 12-pdr heavy designation?
CREATE TABLE table_name_8 (bore VARCHAR, designation VARCHAR)
SELECT bore FROM table_name_8 WHERE designation = "12-pdr heavy"
### Context: CREATE TABLE table_name_8 (bore VARCHAR, designation VARCHAR) ### Question: What is the bore of the boat howitzers with a 12-pdr heavy designation? ### Answer: SELECT bore FROM table_name_8 WHERE designation = "12-pdr heavy"