hey chuck, not sure if this is the kind of opinion you were lookin for but here it is :P
the big advantage i see is that data in a database is 2 dimensional and rectangular while data in XML/DOM can be setup recursively like a tree. For instance, one of the first things i coded since i came back from the conference was a priority list/message board that is set up with folders and files just like a file system. For organization it beats our old priority list setup that was just one long list where each item had a priority #. I know you can set up recursive designs in a database but it takes loops (and recursion) to retrieve your data in this way and takes many sql statements to get all the data you want. >From within XML/DOM you can just give one statement and it returns all the results you are looking for, whether it be a recursive search or not is up to you. Another advantage with using XML and DOM is that lots of things are now being able to unload/load xml data so XML is a good way to transfer data between unlike services in some cases, so your application can use the XML/DOM to load in data from other applications readily (: Another pro is that conceivably, you could use no database and just use a text file to store the XML and use DOM to manipulate the data like sql would manipulate a database. yet another advantage is that theres a "style sheet" type language to render XML into html (server or CLIENT! side...its called XSLT if you remember from the con). You can convert XML to DOM and back so you could grab some XML, manipulate it, send it off to the browser with some xslt, and on the BROWSER side, it will render your XML into data...heck it will even sort your data if you want it to, making the server not have to sort the data, making alot less load on the server. pretty cool stuff i think, but in between pro and con is that i dont know really when recursive structures are really needed...mostly we deal with flat 2d rectangular tables of data and join them together or do summaries when we want to get complicated. A con woud be that i heard that the more data you add to a DOM object it gets exponentialy slower. I dont know how much data is considered too much, im sure it varies from system to system but it would be nice to know the average of what you should be able to store in a DOM object. another con is that the language you use to talk to DOM is very different than sql. Im sure it needs to be, but its another little bit of language to learn (xpointer and/or xpath). Not too hard, but i found it hard to find sources on the net on how to use this stuff. All in all i think its cool, but doesnt have the raw processing power of database engines - maybe that will change? i hope so..and in version 5.5 of witango i think Phil said they are using a better XML parsing engine- but i think there are some really good times to use it. ----- Original Message ----- From: "Chuck Lockwood" <[EMAIL PROTECTED]> To: "WiTango-Talk" <[EMAIL PROTECTED]> Sent: Monday, October 13, 2003 3:20 PM Subject: Witango-Talk: Dom object stored in DB column > At the conference, someone demonstrated using a Dom stored in a column and > did a search for records based on an element value. What is the > advantages/disadvantages to using this technique? > > Opinions? > > Chuck Lockwood > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > LockData Technologies, Inc. > 309 Main Avenue, Hawley, Pa 18428 > 570-226-7340 ~ Fax: 570-226-7341 > [EMAIL PROTECTED] ~ www.lockdata.com > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > ________________________________________________________________________ > TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf ________________________________________________________________________ TO UNSUBSCRIBE: Go to http://www.witango.com/maillist.taf
