On Sun, 2003-07-13 at 10:17, [EMAIL PROTECTED] wrote: > > I understand that SQL is the interface between apps and RDBMS's because > > of history, not because it is correct design. Could you point me to a > > link or book or paper that deals with this paradox? Thanks! > > I'm not sure what you mean by 'correct design'. > > I think you should go back and read the works of Codd and Date on the > development of relational databases. One point that was made early on is > that RDBMS theory doesn't guarantee efficiency, but it does guarantee
SQL is only one possible relational query language. It didn't become de facto standard until the mid- to late-80s. It is an outgrowth of SEQEL (Structured English QuEry Language), which was IBM's 1st try at a descriptive query language. DEC had RDML (Relational Data Manipulation Language) to access it's RDBMS. I'm sure that Burroughs, etc, had their own access methods, too. -- +-----------------------------------------------------------+ | Ron Johnson, Jr. Home: [EMAIL PROTECTED] | | Jefferson, LA USA http://members.cox.net/ron.l.johnson | | | | 4 degrees from Vladimir Putin +-----------------------------------------------------------+ ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
