Firefox locks places.sqlite

问题:

Platform: Firefox 3.6.13, Python 2.7 stackless, and Windows 7 (not yet tested on Ubuntu, I will...)

I tried with the apsw library:

conn = apsw.Connection( dir + profile + '/places.sqlite', apsw.SQLITE_OPEN_READONLY )

And I got the error:

File "c:\apsw\src\statementcache.c", line 386, in sqlite3_prepare apsw.BusyError: BusyError: database is locked

I see "SQLite manager" can open the database also with Firefox running.

I just want to open and read, I think a trouble free operation. And I cannot use "SQLite manager". I need to code my Python (or PHP or Perl) script.

1) Which type of lock does Firefox use on the SQLite file? Why?

2) How does "SQLite manager" work?

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Q2) SQLite Manager works in JavaScript, inside Firefox, so it can access the database.

This is not what I am looking for: An external application reading places while Firefox is running.

回答1:

Firefox uses SQLite to obtain an EXCLUSIVE lock on the database, which is why you cannot open it: http://www.sqlite.org/pragma.html#pragma_locking_mode

回答2:

I am not sure about the lock type Firefox uses, but I'd recommend this:

Copy the Firefox database file to a different temporary location and read it from there (this also lowers the risk of accidentally damaging the original file).

I haven't had problems with this method yet on Firefox 3.*.