SELECT *
FROM file('a', 'CSV', 'a Decimal(10,1)')

Received exception from server (version 19.11.2):
Code: 49. DB::Exception: Received from localhost:9000. DB::Exception: Odd number of elements in section structure: must be a list of name type pairs. 

0 rows in set. Elapsed: 0.062 sec. 

SELECT *
FROM file('a', 'CSV', 'a Decimal64(1)')

Received exception from server (version 19.11.2):
Code: 107. DB::Exception: Received from localhost:9000. DB::Exception: File /var/lib/clickhouse/user_files/a is not exist. 

0 rows in set. Elapsed: 0.069 sec.