What database features/elements are
necessary for a programmer to
understand in order to create
The more experience with database design and normalization the better. Too little (e.g. tables failing to be 1NF) can be just as bad a too much (EVA).
Basic SQL can solve most problems anything beyond can be handled by asking questions on SO.
Developers should also at least know what ACID stands for, with some idea of what it means.
The other thing developers should know is that bad things sometimes happen to transactions and your application should expect every transaction to always work. Here's a quote from an article by Rico Mariani
One Last Warning
If you consider what I said, about the
natural occurrence of failures in a
database, then you’ll soon realize
that it is normal, using Linq
parlance, for db.SubmitChanges() to
throw an exception from time to time.
If you are trying to write a robust
application with high reliability you
need to think about that.
In addition to obvious things like,
“the network went down”, “the database
went down”, there are less obvious
things like, “there was a deadlock”,
“there was an optimistic lock
conflict” that can and do happen.
Those latter two things should be
appropriately retried because nothing
bad has happened. The strategy you
choose, especially for cases where the
optimistic lock failed, can have a
profound impact on your performance
and certainly you can’t just let those
exceptions flow to the user. I think I
can safely say that my mom doesn’t
want to hear about how table X on
connection A deadlocked with table Y
on connection B.
If you’ve been reading carefully then
you’ll see that it’s also “normal” for
a foreach operation over a Linq query
to fail from time to time – you need a
retry strategy for those too to be
Don’t get down on Linq though, those
problems exist with all data
solutions, the productivity benefits
you get from Linq will go a long way
to helping you to add the robustness
you need in the areas you need it.
Don’t read “too much” at once. Don’t
write “too much” at once. Handle
deadlocks, they’re normal. Handle
optimistic lock failures, they’re also
normal. You should land in the Pit of
As for that line in the sand? I would say Developers don't need to know anything about the physical operation, sizing, partitioning, monitoring, (backup/restore), security, High Availability, Disaster recovery, initial setup, etc