Hi Enrico, I like the ON INSERT trigger.....good idea. So perhaps you have a "setLogMaxSize" type function in C that allows the client program to say "hey, I only want the log to hold a max of 10 000 records".....and then I do a select count(*) inside the ON INSERT type trigger and delete entries if "num records > max"......
Regarding the locking, I am using a WAL mode database, so I would say we are talking microseconds anyway? So I am not too worried.....or should I be? Thanks Lynton On 10/05/2011 15:28, Enrico Thierbach wrote: >> A round robin queue is fine. Every so often, to kill off old records do >> >> SELECT max(rowid) FROM myTable >> >> then in your code subtract from it however many rows you want to keep, then >> do >> >> DELETE FROM myTable WHERE rowid< firstToRetain >> >> It won't work perfectly but it's simple and fast. >> > You could even do something like that in an ON INSERT trigger. And with an > AUTOINCREMENT primary key (see http://www.sqlite.org/autoinc.html) > you would not even have to SELECT max(rowid), as the max rowid is then the > rowid of the new record. > > As a side note: even when run from a separate thread, inserting the log > entries and deleting old entries would lock the database, thus affecting any > main thread. You would probably want a separate database for that. > > /eno > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
