Re: Graph database
On Fri, Mar 13, 2020 at 10:22:12PM +0100, Alexander Burger wrote: > Perhaps this helps? https://software-lab.de/doc/tut.html#ext > > It is really very simple. Understanding PicoLisp symbols is perhaps the important point. https://software-lab.de/doc/ref.html#symbol The rest is just making symbols persistent. ☺/ A!ex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Graph database
On Fri, Mar 13, 2020 at 04:02:44PM -0500, Lawrence Bottorff wrote: > Could you point me to a beginner's treatment of this topic, especially an > example of a graph database, and what exactly a picolisp pointer is? Perhaps this helps? https://software-lab.de/doc/tut.html#ext It is really very simple. > I'm afraid I don't even know what you mean by a pointer in this context. I > know from C what a pointer is, but a picolisp pointer is beyond my > comprehension. Exactly the same as C pointers. The 32-bit version of PicoLisp *is* even written in C. The external symbols *point* to each other when loaded inte memory, via properties or arbitrary Lisp structures. And they are loaded *into* memory on demand, implicitly when they are accessed (lazy loading). The higher DB levels then implement entity and relation classes, B-Trees etc., all on top of external symbols. ☺/ A!ex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
Re: Graph database
Could you point me to a beginner's treatment of this topic, especially an example of a graph database, and what exactly a picolisp pointer is? I'm afraid I don't even know what you mean by a pointer in this context. I know from C what a pointer is, but a picolisp pointer is beyond my comprehension. On Fri, Mar 13, 2020 at 3:28 PM Alexander Burger wrote: > Hi Lawrence, > > > I take it the picolisp graph database follows more the Neo4j property > graph > > idea than any RDF/OWL triples, correct? That seems obvious, but I thought > > I'd check. I haven't dived in deep, buy you seem to use Lisp objects to > > create a vertex. But then what are the edges? Again, I'm just getting > > started. > > Sorry, I know absolutely nothing about Neo4j or RDF/OWL, but the edges are > in > fact trivial. > > As everything in PicoLisp is a pointer (except short numbers), the edges > are > indeed just pointers to other symbols. All those symbols in a DB (called > "external symbols") are loaded lazily on demand. > > ☺/ A!ex > > > > > -- > UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe >
Re: Graph database
Hi Lawrence, > I take it the picolisp graph database follows more the Neo4j property graph > idea than any RDF/OWL triples, correct? That seems obvious, but I thought > I'd check. I haven't dived in deep, buy you seem to use Lisp objects to > create a vertex. But then what are the edges? Again, I'm just getting > started. Sorry, I know absolutely nothing about Neo4j or RDF/OWL, but the edges are in fact trivial. As everything in PicoLisp is a pointer (except short numbers), the edges are indeed just pointers to other symbols. All those symbols in a DB (called "external symbols") are loaded lazily on demand. ☺/ A!ex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
