function corr(double precision, double precision) does not exist -- PostgreSQL
<p>Hi when I run simple correlation query in PostgreSQL</p>

<pre><code>select 
    corr(m07_selling_price_total_usd, m12_amount_of_commission_earned_usd)
from order;
</code></pre>

<p>I get following error:</p>

<p><code>ERROR:  function corr(double precision, double precision) does not exist</code></p>

<p>Any ideas about how to solve it? Both variables are double precision so according to documentation (<a href="http://www.postgresql.org/docs/9.4/static/functions-aggregate.html" rel="nofollow noreferrer">http://www.postgresql.org/docs/9.4/static/functions-aggregate.html</a>) it should work.</p>