Begining of Java Servlet Inteface

Christopher Molnar
Mon, 14 May 2001 11:33:33 -0400

Chris Shenton wrote:
> writes:
> > I would suggest the thought that "multiuser" be considered completely
> > synonymous with "using SQL DBMS."  The database provides an interface
> > that supports many concurrent connections; that supports multiple
> > users without needing to think very much about it.
> Need to ensure the code to access the DB uses some kind of
> database-neutral API layer so we don't get locked into
> <insert your favorite DB>.  Would be nice if it could talk to MySQL,
> Postgres, Oracle, or whatever the user/customer has.

As long as none of the db information is hardcoded into the code you are
ok. I am using Tomcat here and all that information is read from the
web.xml file. The nice part about this is that tomcat will run on a
Winblows platform along with Apache and MySQL very well.   I agree with
you we should NOT lock anyone into a specific database and that is
doable if we make sure that SQL is written as SQL, not Postgres SQL or
MySQL SQL. Stay with the standard and it should work.

> Also a DB doesn't necessarily shield  you from multi-user,
> last-one-wins  data corruption.  Without DB "transaction" support,
> there's no good way to have multiple people updating the same data and
> guarantee they won't step on each others toes.  You'd have to work
> around this for transaction-challanged DBs with extensive row/table
> locking.

Can you give me a quick example of a user scenario where this may
happen? As I am trying to work through this and write some java beans
for transactions I am not comming across anyplace where transactions are
really an issue. I may be missing something in my thinking though.