Re: the advantages of garbage collection

On Mon, Jun 23, 2008 at 8:06 AM, Aaron Bartell <aaronbartell@xxxxxxxxx> wrote:

I am wondering if the fundamental infrastructure difference in the languages
is what necessitates garbage collection more in Java and xxx.NET vs. RPG.
For example, in RPG you pass around less information in memory than Java (in
my experience) in that you don't (or rather aren't able to) pass entire
Collections (i.e. result sets) from one method/object to another.

in Java you pass a reference to the object. In RPG and C you pass a
pointer. Both are trivial in terms of not having to copy the data as
the collection is passed from module to module. The difference is the
RPG has to handle the reference counting and object cleanup ( dealloc
once the object is no longer referenced. )

Unfortunately I am not well versed on memory management and the like so I
can't speak with much authority other than offering up questions. Can
anybody speak to that?

... join to columns in another result set, sort the rows, then pass the

object on to another program which creates an XML document from the
collected data.

Is all this being done in memory? How involved are temporary MSSQL tables
involved in the process, or is it more part of C# that is performing these
functions?

All in memory. Crudely stated, as long as there is a reference in the
call stack to the result set object, that object will not be garbage
collected. It is a very elegant system. None of the time consuming
reference counting you see in C++ smart pointers.

I doubt there is a need for temporary SQL tables. A static btree
routine can sort and filter a collection, returning a reference to a
new collection, just as effectively as a DBMS can.

-Steve