On 11 Feb 2011, at 2:37am, Yuzem wrote: > Simon Slavin-3 wrote: >> > >> By looking at the file on disk ? Are you taking into account the journal >> file ? >> > > Yes, I do all the counts
So if I deleted one record and created another you wouldn't spot it ? > and save the data to a file and then if the file is > newer then the database I use the file else I count again. Your process is trustworthy only when you are certain that the database file is not currently open. If there's a chance that some application may be modifying the file when you check these things then the results you get may not be up-to-date. The only way to correctly tell if the data in the database has changed is to use SQLite calls. Also, your operating system does not update the file attributes every time the contents of the file changes. It will often wait for a change of sector or a buffer to be flushed. > No, I am not taking the journal file into account, I don't know what you > mean by that. SQLite uses a journal file to temporarily store change to the database. You will find this journal file appearing in the same directory as the database file if you have the database open and have made changes. These changes will eventually be saved in the database file -- definitely when you close all the SQLite handles to that file -- but until then you have no way of knowing what data SQLite considers is actually in the database apart from using SQLite calls. Read here, especially sections 2.1 to 2.3, about the temporary files SQLite makes: http://www.sqlite.org/tempfiles.html Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
