=?iso-8859-2?Q?Egy=FCd_Csaba?= <csegyud(at)vnet(dot)hu> writes:
> I found that count(*) results less rows than grep.
That's a tad hard to believe. I'm suspecting pilot error of some sort.
Perhaps you have more than one table named t_stockchanges (in different
databases or schemas) and you weren't looking at the same one in both
cases?
Another possibility is that t_stockchanges has child table(s). Your
SELECT would count rows in the child tables, but I don't think that
pg_dump -t would dump them.
regards, tom lane