zer moves to using sequential scans (working off the disk) things
get a lot slower.
For me, the penny has finally dropped on why I should use EXPLAIN for
bulk operations.
Thanks too, to Greg Smith, Robert Klemme and Thomas for all the feedback.
Kind regards
Harry Mantheakis
London, UK
-
hing remains crystal clear: I love Postgresql :-)
Kind regards
Harry Mantheakis
London, UK
On 23/06/2011 16:05, Harry Mantheakis wrote:
Hello
I am attempting to run an update statement that copies two fields from
one table to another:
UPDATE
table_A
SET
(
field_1
, field_2
)
.
Thanks again.
Harry Mantheakis
London, UK
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> try a series of smaller examples...
Mark, that was the tip the saved me!
Many thanks.
Harry Mantheakis
London, UK
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enough to be surrounded by
MatLab users, one of whom generated the 800-statement file in one minute
flat!)
Many thanks again for all the info.
Kind regards
Harry Mantheakis
London, UK
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obliged!
Harry Mantheakis
London, UK
On 24/06/2011 12:39, Claudio Freire wrote:
On Fri, Jun 24, 2011 at 1:19 PM, Harry Mantheakis
wrote:
there are lots of ways in which it could be struggling...
I have been monitoring the server with IOSTAT -d and IOSTAT -c and I cannot
see anything alarming
use is matching the
only two indexed fields, and my understanding is that querying on
indexed fields is faster than querying on fields that are not indexed.
(Note also, that the indexed field is NOT being updated.)
But if this update fails, I shall try what you suggest!
Kind regards
Harry Mant
of disk page fetches'.
Do you, by any chance, have any notion of how many disk page fetches can
be processed per second in practice - at least a rough idea?
IOW how do I convert - guesstimate! - these numbers into (plausible)
time values?
Kind regards
Harry Mantheakis
London, UK
no reason to believe that the server
is struggling.
My question is: can I reasonably expect a statement like this to
complete with such a large data-set, even if it takes several days?
We do not mind waiting, but obviously we do not want to wait unnecessarily.
Many thanks.
Harry Mantheakis
Lon
