On Thu, 2011-04-07 at 09:35 -0500, Kevin Grittner wrote:
> I'm pretty sure Jeff was talking about enforcing business rules too
> complex to be covered by the declarative constraints.
Exactly. SQL offers a limited set of declarative constraints that do
specific things, aside from ASSERT (aside: maybe we can implement ASSERT
now using SSI; but it would require all transactions to be in SSI mode).
Outside of that limited set, triggers and SSI are probably the best bet.
Even setting aside the issue of constraints, different shops have
different roles for DBAs. I generally think that a DBA has some
responsibility over the types of transactions that are permitted in the
system, what kinds of locks or other resources that those transactions
might hold, etc.; SSI is clearly of interest to such DBAs. And beyond
that, the DBA is often the expert, and may be able to show programmers
how to avoid race conditions inside the DBMS effectively (and SSI may be
one solution).
Regards,
Jeff Davis
