>Three years ago we wrote a program to extract email addresses from a
>database and load them into a list.  That's not too hard and should
>also be possible to do with other databases without the DBMS interface.
>But it does require some programming effort, setting up cron jobs, etc.
>in each individual case.  So a general interface would be nicer.

The only "general" database interface is ODBC, and even that is only
general in theory, with a lot of conditional code and hair-pulling. Other
than that, every vendor provides an API and you have the usual trade-off
between development/testing time and market share. The code must be
compiled (and the API/client licensed) separately for each operating system
you want to support, and the API can even change radically from one
version to another. For instance, version 8 of OCI is a major rewrite of
version 7 with most of the functions and constants renamed.

Anyway, the native API for SQL Server is ODBC, so if you want to
interface to SQL Server the simplest solution is by far a LISTSERV
server on a system with ODBC (ie NT). The alternatives are much
more complex and generally very expensive, although you may already
own the necessary licenses for unrelated reasons.

  Eric