Tom Lane wrote:
There is not anything in there that considers whether the table's physical order is so nonrandom that the search will take much longer than it would given uniform distribution. It might be possible to do something with the correlation statistic in simple cases ...
In this case, the rows are not random at all, in fact they're inserted from a sequence, then rows are deleted as they are processed. If the planner is hoping for random physical distribution, this particular case is exactly wrong.
Craig
