On Mon, 9 Jun 2008 10:36:26 -0400, Simon, Lorna <Lorna.Simon@UMASSMED.EDU> wrote:

>I have a question about sql - what is the advantage of learning it? Are >there things you can do in sql that you can't do in a regular sas data >step?

Very rare things. Some kinds of merging are hard to do in DATA step. E.g. n:m merges, which produce a cartesian product is hard to do in DATA-step. (I don't say impossible! Otherwise the next poster shows me, how to do it. I don't even try it, because it's so easy in PROQ SQL).

I see one advatage: all relational-DB specialists know SQL. They normally don't know SAS. For them it is easier to step into the SAS world with SQL. The other thing is: if you deal with interfaces to relational DBs, it might be helpful to code things directly in the DB-language.

I prefer SAS, because for me SQL is not easy to read and to understand. It's sometimes really a kind of "black box" and hard to say what happens. That is easier for me to understand in DATA-step. But I sometimes saw very elegant and short solutions for things which are complicated in DATA step. For that it is good to know about.

And: it's never a fault to know both worlds! So you can pick out the best things of each. Gerhard