Date:         Fri, 16 May 2008 11:09:17 -0400
Reply-To:     Mark Smolkin <marksmolkin@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Mark Smolkin <marksmolkin@GMAIL.COM>
Subject:      SQL confusion
Content-Type: text/plain; charset=ISO-8859-1

Hi..I am fairly new to SQL and am confused by a sentence in the SAS 9.1
SQL Procedure User's Guide. The text below is from pg. 41 and I don't
quite understand the second criteria mentioning the "where" clause. To
examine it, I created fake data and I saw that I could use a summary
function like "sum(cost)" as the lone item in the select clause, use a
where clause that subsetted on an a separate variable, and still receive
the correct overall sum without an error message. I am sure I am simply
misinterpreting the sentence and so I was hoping somebody could set me
straight....Appreciate the help!...

Mark


"In the previous example, PROC SQL combined information from multiple rows
of data into a single row of output. Specifically, the world oil reserves
for each country were combined to form a total for all countries.
Combining, or rolling up, of rows occurs when

􀀀 the SELECT clause contains only columns that are specified within an
aggregate function
􀀀 the WHERE clause, if there is one, contains only columns that are
specified in the SELECT clause."