Just curious, how are you planning to display the histogram? <br />Are you allowed to use application code (C/C++/Perl,
etc..)to generate the histogram? Personally, SQL is great for showing the data but not good for making graphs with data
youcan show.<br /><br /><br /><br /><div class="gmail_quote">On Wed, Apr 30, 2008 at 5:01 PM, Alexy Khrabrov <<a
href="mailto:deliverable@gmail.com">deliverable@gmail.com</a>>wrote:<br /><blockquote class="gmail_quote"
style="border-left:1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Greetings -- I have a
tableof the kind<br /><br /> Ratings:<br /> id integer<br /> rating smallint<br /><br /> -- where value can take any
valuein the range 1 to 5. Now I want to have a statistical table Stats of the form<br /><br /> id integer<br /> min
smallint<br/> max smallint<br /> avg real<br /> r1 integer<br /> r2 integer<br /> r3 integer<br /> r4 integer<br /> r5
integer<br/><br /> -- how can I create it in one pass over Ratings? I can use min(), max(), avg() for<br /> insert
intostats values (id,select min(rating), max(rating), avg(rating), ...) from ratings<br /><br /> -- but what to do for
r1,..,r5,short of subselects (select count(rating) from ratings where stats.id=<a href="http://ratings.id"
target="_blank">ratings.id</a>)for each, which is an overkill?<br /><br /> Also, if a table Stats already exists with
somemore columns, and we need to do an update, not insert, for the above, how would that work --<br /><br /> update
statsset min=min(ratings), ... from ratings where stats.id=<a href="http://ratings.id" target="_blank">ratings.id</a>
--how do we do the histogram in this case, where the id is fixed explicitly?<br /><br /> Cheers,<br /> Alexy<br /><font
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