&gt; My problem is not that PostgreSQL does not understand the distribution of my data. It does. The problem is that it comes up with a query plan without realizing that I&#x27;m only querying for a very small range of timestamps.<p>Which version did you reproduce that on? While the problem has not been generally addressed, the specifically bad case of looking up values at the &quot;growing&quot; end of a monotonically increasing data range has been improved a bit over the years (9.0 and then some incremental improvement in 9.0.4).