Delete old records from firefox sqlite databases

Question

I have some big sqlite3 databases in ~/.mozilla/firefox/profilename

Notably places.sqlite (12 MB) and urlclassifier3.sqlite (33 MB).

Is it possible to truncate them and wipe out the oldest records in them?

Of course I could just wipe them completely, but that's not my goal - I just want to minimize the size of those files while keeping the newest records.

Answer 1

The places.sqlite database contains all your bookmarks and history -- you can just remove unneeded history from Firefox. urlclassifier3.sqlite is a list of phishing site URLs, and you can delete it completely -- while anti-phishing is enabled, it will be re-populated automatically (it may be smaller afterwards, so deletion is not useless).

If you want to disable anti-phishing completely, you can turn off these two checkboxes in settings:

If you want to optimize them even more, check this article.

Answer 2

From this article, all you have to do is go into Tools=>Error Console and paste in Components.classes["@mozilla.org/browser/nav-history-service;1"].getService(Components.interfaces.nsPIPlacesDatabase).DBConnection.executeSimpleSQL("VACUUM");

Answer 3

Another alternative (if you're using Windows) is to use the already-useful-for-other-reasons CCleaner (AKA CrapCleaner). It includes an option to clean up and compress the Firefox databases as part of its regular cleaning tasks.