On 30 May 2011, at 2:08am, Frank Chang wrote: > Thank you for your help with the PRAGMA page size question. Sometimes I see > C++ programs which first issue the PRAGMA page_size = 4096. Then these C++ > programs request a sqlite3_execute(Database,"VACUUM",callback,0,&Msg) which > takes about 4 minutes to complete. > We wondering if the > sqlite3_execute(Database,"VACUUM",callback,0,&Msg) is necessary to change the > PRAGMA page_size=4096.
I just looked it up: http://www.sqlite.org/lang_vacuum.html You're right: VACUUM allows you to change the page size of a database file. I didn't know that. Clever. Yes, it won't happen without the VACUUM. This rewrites the entire database file. Under normal circumstances the amount of time doesn't matter. You don't normally use VACUUM once you have your system up and running. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users