Re: Thread safe connection-name mapping in ECPG. Is it required?

On Mon, Feb 23, 2004 at 09:27:40PM +0530, Shridhar Daithankar wrote:
> It looks like the mutex protects the connections list in connection.c. I do
> not like that from a application developers perspective.
>
> If I am developing an application and using multiple connections in multiple
> threads, I have to store a connection name for each connection as C string.
> Of course, I also have to protect it across thread so that I can rightly tell
> ecpg what connection I would be talking to next.
>
> If an application can take care of a C string, it can also take care of a
> connection structure. On top of it, it eliminates the list lookup. The
> potential performance gain could be worth it if there are hundreds of
> connections and a busy website/application server.
>
> What I wonder is, do we really need to maintain that level of lookup? Can't we
> just say a connection is a 'struct connection *' which should be opaque and
> should not be touched or poked inside, just like PGConn.

I'm not sure I understand you correctly. The SQL standard says you can
call your statement as this:
exec sql at CONNECTION select 1;

Here CONNECTION of course is a string, the name of the connection. So,
yes, we have to maintain that list to make sure we get the right
connection.

Or what were you asking?

Michael
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