Re: Pre-relational, post-relational, 1968 CODASYL "Survey of Data Base Systems"

and slight drift from pre-rdbms to pre-sql ... the whole ramus/nomad/focus 4th gen genre ... specific tale: http://www.decosta.com/Nomad/tales/history.htm

note that the system/r & sql stuff was done on the platform developed at the science center ... previous post
http://www.garlic.com/~lynn/2004e.html#12

the whole ramus/nomad/focus genre was done on the same platform ... but at various time-sharing service bureaus (that happened to be using the same platform as their service delivery), various past

ramus/nomad/focus related posts:
http://www.garlic.com/~lynn/2002i.html#64 Hercules and System/390 - do we need it?
http://www.garlic.com/~lynn/2002i.html#69 Hercules and System/390 - do we need it?
http://www.garlic.com/~lynn/2002l.html#56 10 choices that were critical to the Net's success
http://www.garlic.com/~lynn/2003d.html#15 CA-RAMIS
http://www.garlic.com/~lynn/2003d.html#17 CA-RAMIS
http://www.garlic.com/~lynn/2003k.html#48 Who said DAT?
http://www.garlic.com/~lynn/2003m.html#33 MAD Programming Language
http://www.garlic.com/~lynn/2003n.html#12 Dreaming About Redesigning SQL
http://www.garlic.com/~lynn/2003n.html#15 Dreaming About Redesigning SQL

for total topic drift ... the science center had also originated the whole markup language thing ... originally called GML (the letters are the initials of three of the people at the science center). Both "G" and "L" transferred out to san jose ... and I remember "L" working on early BLOBs on R* (r-star, follow-on to system/r).

one of the big arguments that i remember from the pre-relational dbms people in stl ... was the physical disk space requirements. The earlier databases had physical pointers ... which relational replaced with indexes. The indexes tended to double the physical space requirements (as well as increasing overhead) vis-a-vis the databases with direct physical pointers. The indexes, however, reduced the manual maint. involved in maintaining the physical pointers. The issue then was somewhat the disk space & processing overhead vis-a-vis the manual maint overhead. As disk space & processing became cheaper, the trade-off tended to shift towards optimizing people effort as opposed to optimising hardware.

-- 
Anne & Lynn Wheeler | http://www.garlic.com/~lynn/