On Mon, 9 Feb 2004, David Garamond wrote:
> [=============> ] 56% ETA ...
>
> I know there is no such thing in Postgres right now (though there is
> pg_stat_activity). But is there database product that can do this?
>
When pg is processing a query it doesn't know how long it will take, so it
can't make an estimate. Consider a query on a very large table with no
indexes such as "SELECT * FROM tab WHERE col = 1 LIMIT 1;" As it will be
forced to do a sequential scan of the table there is no way of telling if
a matching row will be found on the first row or never which will take
wildly different amounts of time.
Kris Jurka
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TIP 9: the planner will ignore your desire to choose an index scan if your
joining column's datatypes do not match
