From: Warren Young
Date: August 12 2010 8:57pm
Subject: Re: I fixed this problem by setting pending_options in disconnect().
List-Archive: http://lists.mysql.com/plusplus/9015
Message-Id: <4C646026.1000303@etr-usa.com>
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On 8/11/2010 11:00 PM, Heejin Ju wrote:
>
> void
> DBDriver::disconnect()
> {
> 	if (is_connected_) {
> 		mysql_close(&mysql_);
> 		memset(&mysql_, 0, sizeof(mysql_));
> 		is_connected_ = false;
> 		error_message_.clear();
>
>          // added code begin
>          pending_options_ = applied_options_;
>          applied_options_.clear();
>          // added code end
> 	}
> }

It's not clear to me exactly what you're trying to do here.  My guess is 
that you want MySQL++ to automatically reapply previously-set connection 
options when bouncing the connection.  If so, I think MySQL++ is already 
doing the right thing, and that your change can cause problems.

An explicit Connection::disconnect() followed by a connect() call on the 
same object doesn't always indicate a reconnect to the same server, with 
the same parameters.  I'd guess that most of the time, code that does 
this is trying to connect to a different server, or at least renegotiate 
a different type of connection to the same server.  I don't see why we'd 
want to restrict this call pattern in MySQL++ so you always get the same 
options on the new connection.  The new connection might need different 
options.

Furthermore, the way the library currently works doesn't prevent you 
from reapplying the options yourself.  You don't need MySQL++ to change 
for this.

It might be nice to have DBDriver::reconnect() (wrapped in Connection), 
which disconnects, re-enqueues all the options, then connects.  My main 
objection to doing that is that I don't see where you'd actually use it. 
  If you just need the connection to be automatically reestablished if 
it drops for some reason, MySQL++ already provides ReconnectOption.  So, 
I'd need a use case where ReconnectOption isn't sufficient to justify 
adding this method.