Seems that the compiled-in default character set of your libmysqlclient is latin1 instead of utf8. Actually, what done by the SET NAMES query is to change the client character set to another.
-- UEMURA (fka. MAENAKA) Tetsuya <[EMAIL PROTECTED]> Posted on Wed, 28 Nov 2007 10:43:10 +0100 by author bugtrack <[EMAIL PROTECTED]> > http://www.dbmail.org/mantis/view.php?id=655 > ---------------------------------------------------------------------- > maenaka - 28-Nov-07 01:40 > ---------------------------------------------------------------------- > MySQL's automatic reconnection is unsafe because of the following reason. > > First, SET NAMES query is a required arbitration between server and client > if both's character encoding is different. This should be done at the time > of connection open. (Of course you can issue SET NAMES between every query > with the huge overhead though.) > > By the way, MySQL's automatic reconnection is made transparent to the > client. So the client never know that SET NAMES should be issued again. > > Therefore, if the connection is restored this way, the character encoding > mismatch may occur (and some or all data is garbled or lost). > > ---------------------------------------------------------------------- > idk - 28-Nov-07 10:43 > ---------------------------------------------------------------------- > You are right, but... > > I have both client and server in the same charset (database, tables and > fields too), I don't know why SET NAMES latin1 (and not utf8) is sent in > the background (transparent for client) after auto reconnection is made > and before last (failed) query is repeated, but this issue exposes > transparent (for client) auto reconnection problem. > > Though recommended solution is not transparent for client, but for all > database calls is. The solution is sufficient for single queries (as > SELECT NOW()), there is no need to know that reconnection was made. But > all transactions and sequent queries (as SELECT LAST_INSERT_ID()) are at > risk from data inconsistency, as I wrote above. > > For me, if I don't restart MySQL server in middle of the transaction and > every quasi auto reconnection (invoked after unsuccessful ping incl. SET > NAMES utf8) is caused by connection idle timeout (so not in time of > usage), this issue (charset mismatch) will be solved. > > Yeasterday, I have removed reconnection setting out and append TRACE > message when ping miss. Now I'll wait for some days when issue will > happen. _______________________________________________ Dbmail-dev mailing list Dbmail-dev@dbmail.org http://twister.fastxs.net/mailman/listinfo/dbmail-dev
