gistfile1.txt

postgres=# CREATE TEXT SEARCH CONFIGURATION nofile ( COPY = simple);
CREATE TEXT SEARCH CONFIGURATION
Time: 210.210 ms
postgres=# ALTER TEXT SEARCH CONFIGURATION nofile DROP MAPPING FOR file;
ALTER TEXT SEARCH CONFIGURATION
Time: 2.649 ms
postgres=# SELECT * FROM ts_debug('simple', 'term1/term2');
 alias |    description    |    token    | dictionaries | dictionary |    lexemes    
-------+-------------------+-------------+--------------+------------+---------------
 file  | File or path name | term1/term2 | {simple}     | simple     | {term1/term2}
(1 row)

Time: 5.128 ms
postgres=# SELECT * FROM ts_debug('nofile', 'term1/term2');
 alias |    description    |    token    | dictionaries | dictionary | lexemes 
-------+-------------------+-------------+--------------+------------+---------
 file  | File or path name | term1/term2 | {}           |            | 
(1 row)