Relational DBs always reserve the total space for a record for faster searching. That is why when creating a db you have to tell the DB what type and size of each field is.
Thanks Marc Aylesworth C3I Associates AFRL/IFSE Joint Battlespace Infosphere Team 525 Brooks Rd Rome, NY 13441-4505 Tel:315.330.2422 Fax:315.330.7009 Email: [EMAIL PROTECTED] -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Gregory Woodhouse Sent: Monday, September 19, 2005 3:06 PM To: hardhats-members@lists.sourceforge.net Subject: Re: [Hardhats-members] Re: Wiki additions: [was: web evaluation tool] This is actually not true. flat tables are the abstraction presented to the user (or programmer) with relational databases, but the underlying storage model is, more likely than not, based on B-trees, just as it is in MUMPS. This can be confusing, because the basic abstraction presented to the user in MUMPS is multi-branching trees, but that abstraction is not the same as the underlying storage model. === Gregory Woodhouse [EMAIL PROTECTED] "The most incomprehensible thing about the world is that it is at all comprehensible." --Albert Einstein (1879-1955) On Sep 19, 2005, at 11:56 AM, Kevin Toppenberg wrote: > 2) What is the fundamental difference between a relational database > and > a hierarchical database and how does that effect the end-user? (Should > we even care? If so why?) > > Another difference is the way the data is stored. M data is stored in > b-trees, as compared to flat tables (I believe). This leads to faster > data acess, and less CPU power needed. > > Also, the database in M is called by some a "sparce array." This > means that there are no "blank spaces" left for data to be later > filled into. So with M, if there is no data present, then no space is > wasted. I find this to lead to many many fields being defined for a > given file. With a traditional database, having all these fields with > empty/wasted space, would lead to huge database files. But with M, > one can can store years of patient information on a relatively small > disk. > ------------------------------------------------------- SF.Net email is sponsored by: Tame your development challenges with Apache's Geronimo App Server. Download it for free - -and be entered to win a 42" plasma tv or your very own Sony(tm)PSP. Click here to play: http://sourceforge.net/geronimo.php _______________________________________________ Hardhats-members mailing list Hardhats-members@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/hardhats-members ------------------------------------------------------- SF.Net email is sponsored by: Tame your development challenges with Apache's Geronimo App Server. Download it for free - -and be entered to win a 42" plasma tv or your very own Sony(tm)PSP. Click here to play: http://sourceforge.net/geronimo.php _______________________________________________ Hardhats-members mailing list Hardhats-members@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/hardhats-members
