execute the statement before getting the row
add utils to generate SELECT and INSERT queries
add category listing
add way to specify date in the CLI
check for duplicate before importing.

allow to create categories
use IfMissing variant of createDirectory to prevent creating something that already exist.
report a useful error in the case where the category is not found.
insert category in the category table, not the cat table.
actually commit new categories
allow to specify a filename
export exist to allow to test for existence in the database.
add a useful get error
commit Exist