Subject Re: [IB-Architect] New system functions/objects was: planning t he use of blr codes
Author Ivan Prenosil
> Use two of the
> remaining 82 blr codes to define blr_scalar_function and blr_agg_function.
> That reopens the blr name space for functions.

Good solution to problem with limited blr name space.


> >d) system defined "udfs".
> >
> >System defined UDF, like the doomsday function but without
> >the side effects, would be easy and embeddable in stored
> >procedures.
>
> Doesn't handle the multi-role problem any better than
> the blr suggestion.

Inquiry that can return more values (like databases participating
in transaction, active roles ...) can be retrieved by functions
with arguments, i.e. not simple USER, ROLE, ..., but

ROLE(<value>)
or
blr_scalar_function, blr_function_role, <value>

where <value> can be either index or handle.

Once the info is available in that form, it is easy to write
system-selectable-stored-procedure, and thus there is no need to invent
new mechanism for pseudo system tables.

(I expect that no one wants updatable pseudo system tables?)


Ivan
prenosil@...
http://www.volny.cz/iprenosil/interbase