<APOLOGY>Sorry for not responding to my own post sooner. I had to switch email addresses and in the process didn't recieve any of the follow-up posts</APOLOGY> Jeff wrote: > (2) GST requires Oracle DB; Loci uses PAOS and a simple DB I guess I didn't present this clear enough. My thought for GST was to define an interface for data retrieval and storage and then provide several standard data manager plug-ins that implement this interface. Iinitially it would probably be a local filesystem plug-in and a db plug-in [either mysql or acedb].) In many ways, it sounds simmilar to what is being talked about for Loci. I guess the only difference is that the GST approach would be limited to local plug-in based access (However, a plug-in that utilized CORBA could be implemented). The advantage from what I can tell of using a local plug-in approach as opposed to a PAOS approach is that you are not tied to a specific transfere technology, you are only limited in that the endpoint/startpoint from the client side must be a plug-in that implements the DM interface. Jeff wrote: > And the GST DM is something like Loci's server/daemon, "Locid". Sort of (I am probably not being careful about consistently using the term DM). So the approach would be: 1) A well defined DM interface (which opperates on the client side) 2) DM Plug-in(s) which implement the DM Interface (These also opperate on the client side) 3) Depending on the DM Plug-in, various backend or middle end "servers" may need to be implemented. So with Loci, it sounds like the middle end and backend "servers" technologies are fixed, where with a plug-in approach only the plug-in interface in fixed. Jeff wrote: > In Loci, a single XML document "travels" a workpath, so everything is > done serially (within one path). The document will collect various XML's So do you mean that the original data, and analysis results, etc will all accumulate in one xml document? This doesn't sound like a good idea, but I am probably misunderstanding what you are saying. Why might this be a bad idea (I am thinking as I write, so don't flame me too hard ;o): 1) Complicates data locking in a multi-user model 2) Increases server load by forcing parsing of un-needed data (See recent post from bioperl with comment on server side XML parsing). If parsing isn't done on the server side, then you have the issue of having to transfere all that combined data. It sounds better to me to just implement a robust cross referencing mechanism, assume each data object to be just one "item" (ie blast results, or a sequence, or a restriction map). Then let the backend server store the data as it sees fit (ie as one huge flat file, as individual database entries, as individual files, ...) This also simplifies the issue or redoing analysis (which I would assume would be a common task -- ie monthly blast searches on the same query sequence). Jeff wrote: > But as far as Loci is concerned, can we make it so that the XML types > (DTD's) are not hard-coded into Loci? What if each locus were > responsible for finding its own XML parser/translator? That would > pretty much make Loci a general purpose command-line wrapper. Definately! To take it to a further extreme, Loci should provide the xml parsing and a SAX like interface to the data. Then each loci doesn't have to implement an XML parser, only the SAX callbacks to handle the XML data. Then loci could handle any XML data for which a locus is provided and it could even handle data in the absence of a DTD. (The advantage of the SAX interface over passing the whole tree, is that memory isn't wasted on building parts of the tree that aren't needed.) I am not really familiar with the SAX interface, but hints could be provided so that only elements the locus wants are passed through the SAX callbacks. Justin's comments are basically what I was thinking. Rather than passing a program all the data, just pass it a reference (maybe an XLink/XPointer) to the input data. Under the plug-in model, plug-ins for networked data could implement a cache mechanism to speed up access. -Alan ************************************************************************ Alan Williams ------------------------------------------------------------------------ University of California, Riverside "Where observation is concerned, Dept. of Botany and Plant Sciences chance favors the prepared mind." Alan at TheWilliamsFamily.org -- Louis Pasteur ************************************************************************