SQLite will block access to the whole database during a write operation. Readers will have to wait until the write completes, even if the object they are interested in is not affected by updates. Protecting each object's data with a posix read-write lock will allow readers to access any object that is not currently being modified by the writer without delay, giving potentially much greater concurrency..
-----Ursprüngliche Nachricht----- Von: sqlite-users [mailto:[email protected]] Im Auftrag von heribert Gesendet: Mittwoch, 20. September 2017 09:09 An: [email protected] Betreff: [EXTERNAL] Re: [sqlite] sqlite3_stmt limitations @Clemens: You wrote "Not very much. But preparing a statement is very fast; don't try to be too clever." What do you mean with "don't try to be too clever"? Is preparing for reuse not really necessary? The select will be like "SELECT Value FROM RgbValues WHERE Object=? AND Property=?". Will it be better to prepare the sqlite3_stmt and reuse it? Or ondemand: prepare, use and close the sqlite3_stmt. Is the time-consuming of parsing a statement like above too high, so it will be better to reuse the sqlite3_stmt (so i will have thousends prepared)? Thx heribert > heribert wrote: >> The threads prepares their own sqlite3_stmt's with select statements >> to the properties currently needed > A single statement "SELECT Value FROM T WHERE Name = ?" might suffice. > >> Is their any limitation of sqlite3_stmt bound to a database? > Only memory. > >> How much memory is used by a sqlite3_stmt? > Not very much. But preparing a statement is very fast; don't try to be > too clever. > > > Regards, > Clemens > _______________________________________________ > sqlite-users mailing list > [email protected] > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users ___________________________________________ Gunter Hick Software Engineer Scientific Games International GmbH FN 157284 a, HG Wien Klitschgasse 2-4, A-1130 Vienna, Austria Tel: +43 1 80100 0 E-Mail: [email protected] This communication (including any attachments) is intended for the use of the intended recipient(s) only and may contain information that is confidential, privileged or legally protected. Any unauthorized use or dissemination of this communication is strictly prohibited. If you have received this communication in error, please immediately notify the sender by return e-mail message and delete all copies of the original communication. Thank you for your cooperation. _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
