[asterisk-users] ODBC connection to Microsoft SQL Server

[Tilghman Lesher]

On Monday 12 November 2007 18:14:57 Robert McNaught wrote:
> I wish to integrate a Microsoft SQL server with Asterisk for CDRs and
> for dialplan routing based on database values, and have this application
> scale to a large number of simultaneous calls:  The Asterisk: The Future
> of Telephony 2nd edition book states that:
>
> ‡ The pooling and limit options are quite useful for MS SQL Server and
> Sybase databases. These permit you
>   to establish multiple connections (up to limit connections) to a
> database while ensuring that each connection
>   has only one statement executing at once (this is due to a limitation
> in the protocol used by these database
>   servers).
>
> Does this suggest any kind of performance issue with scaling? 

If there is any such issue, it is due to a limitation with the database
server protocol, not with Asterisk.  The description should have made
that clear.

> I am 
> assuming not as all this indicates is that DB queries are pooled from
> the ODBC connection on the Asterisk Server side rather than the SQL
> Server? 

MS SQL Server is simply unable to accept multiple simultaneous queries on the
same connection, so this is the only solution possible to avoid any
collisions.

> Has anyone done this before in a large implementation? 

I've never done it in a large implementation, but I don't see any reason why
it wouldn't work.  If you're really concerned with the scale of opening a lot
of connections, might I suggest that you use PostgreSQL?

-- 
Tilghman