which syntax for which assertions?

["Jim Sermersheim" <jimse@novell.com>]

I can't find it documented which syntax (the attribute syntax or the
matching rule syntax) is used for which assertions in various
operations. I'll list what I think, but it may be wrong:

AVAs in:                 (A)ttr or (M)atchRule
equality filter          M(of equality mr)
ge and le filters        M(of ordering mr)
substring filters        M(of equality mr)
extensible filter        M(of extensible mr)
compare                  M(of equality mr)
add/mod                  A(of equality mr)
DNs                      A(of equality mr)

So for example, a compare operation which specifies 'attributeTypes'
will send an 'OID' and not an 'Attribute Type Description'. Whereas if
the same attribute were passed in an add operation, it would send an
'Attribute Type Description', rather than an 'OID'.

It's important to make this distinction because LDAP doesn't provide
syntax knowledge in AVAs. If an AVA also carried with it the syntax used
for the assertion value, we could derive the 'OID' from the 'Attribute
Type Description' in the compare example above. But because we don't
have this ability, we must state which syntax is used for each operation
so the server can know how to interpret it.

By the way, the syntaxes doc has expired. A relic can be found here
http://vesuvio.ipv6.tilab.com/internet-drafts/draft-ietf-ldapbis-syntaxes-07.txt

Jim