RE: Relational database as backend?

["Luke Howard" <lukeh@xedoc.com.au>]

> UMich LDAP release 3.3, and thus OpenLdap 1.0, ~does~ support
> pluggable
> backend databases. Layering slapd on top of an RDBMS is a
> SMOP (small matter
> of programming). Tho, one has to carefully consider ~why~
> one'd want to do
> that. As pointed out in prior messages, these slides & doc
> discuss such
> matters...

We implemented a simple LDAP backend on top of mSQL a year or two back. It
was inefficient because it didn't map LDAP queries to SQL expressions, but
that's just another SMOP. The point of the backend was to provide LDAP
access to data adhering to a specific schema, known at compile time.

Thus, it wasn't a general-purpose backend; indeed, I suspect that most
attempts to implement a general-purpose relational backend will result in a
schema which isn't particularly useful to "native" clients of the
database.(Unless you have a predefined mapping between LDAP and relational
schema; but you need to accomodate auxiliary classes, etc.)

Most of the LDAP servers around use the Berkeley DB library (Netscape and
ISODE use the recent Sleepycat library). Active Directory uses Microsoft's
Jet. I don't know about NDS; does anyone know?


-- Luke