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...p answer your question. SQL, and its progenitor SEQUEL, were developed specifically to manipulate relational databases. It was developed in the early 1970s (equivalent to the historical bronze age) when the concept of a relational database (see https://en.wikipedia.org/wiki/Relational_database) and Codd's 12-rules were being developed (see https://en.wikipedia.org/wiki/Codd%27s_12_rules) At the time, the concept of a relation database and a programming language dedicated to manipulating them was revolutionary. The concept was clearly needed, important, and well used; a commercial version of S...

...is happenning. My codes are the following: rm(list=ls()) #remove almost everything in the memory set.seed(180185) nsim <- 10 mresultx <- matrix(-99, nrow=1000, ncol=nsim) mresultb <- matrix(-99, nrow=1000, ncol=nsim) N <- 200 I <- 5 taus <- c(0.480:0.520) h <- c(1:20/1000) codd <- c(1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81) ceven <- c(2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,50,52,54,56,58,60,62,64,66,68,70,72,74,76,78,80,82) cevenl <- c(2,4,6,8,10,12,14,16,18,...

...on. SQL, and > its progenitor SEQUEL, were developed specifically to manipulate relational > databases. It was developed in the early 1970s (equivalent to the > historical bronze age) when the concept of a relational database (see > https://en.wikipedia.org/wiki/Relational_database) and Codd's 12-rules > were being developed (see https://en.wikipedia.org/wiki/Codd%27s_12_rules) > > At the time, the concept of a relation database and a programming language > dedicated to manipulating them was revolutionary. The concept was clearly > needed, important, and well used; a...

dear Members, I have recently started studying SQL and MySQL. My question is, what exactly is SQL used for? That is, whatever can be done by SQL, like subsetting and filtering of data sets, can also be done by R. What's, then, the advantage of SQL? It is OK if you tag this question as offtopic, but I could'nt find any info on the web. Can you please refer me to

...hangeset/4492) Lots have been said about Active Resource and there seem to be quite a debate raging on in the blogosphere. For a great explanation of Active Resource in general go here: http://jimonwebgames.com/articles/2006/06/26/dont-say-crud-say-fucd (I like that one because it speaks of Edgar Codd, who together with Chris Date are the granddaddies of the relational model) For a great introduction to Active Resource itself go to Ryan''s blog: http://www.ryandaigle.com/articles/2006/06/30/whats-new-in-edge-rails-activeresource-is-here and for a more ''philosophical''...

...is happenning. My codes are the following: rm(list=ls()) #remove almost everything in the memory set.seed(180185) nsim <- 10 mresultx <- matrix(-99, nrow=1000, ncol=nsim) mresultb <- matrix(-99, nrow=1000, ncol=nsim) N <- 200 I <- 5 taus <- c(0.480:0.520) h <- c(1:20/1000) codd <- c(1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49,51,5 3,55,57,59,61,63,65,67,69,71,73,75,77,79,81) ceven <- c(2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,50,52, 54,56,58,60,62,64,66,68,70,72,74,76,78,80,82) cevenl <- c(2,4,6,8,10,12,14,16,1...