I got the following error when I read the journal_mode (in python apsw).
```
if c.execute('PRAGMA journal_mode;').fetchone()[0] != 'wal':
File "src/cursor.c", line 1019, in APSWCursor_execute.sqlite3_prepare
File "src/statementcache.c", line 386, in sqlite3_prepare
apsw.BusyError: BusyError: database is locked
```
Since I just read something from the database, why does it matter whether the database is locked or not? Thanks.