> I don't think it is actually random. It just that the order is not defined
> and other events may change the order. I believe that without an ORDER BY
> or other clauses that cause an index to be used that the database tends to
> return rows in the order stored on disk. This order tends to be the order
> in which rows were added. My observation is this ordering is faily stable
> and it seems to survive a database reload. Just don't rely on it. There is
> a CLUSTER command to change the physical ordering.
Yes, usually it is the heap order, but if you do "col > 12" you may get
it in index order by the column indexes, or you may not, depending on
the constant, the size of the table, vacuum, vacuum analyze, etc.
-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
853-3000+ If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill,
Pennsylvania19026
