On Thu, Nov 13, 2008 at 06:39:47PM -0800, Eus wrote:
Isn't that something like this is better handled at the application level
instead of the DB level?
IOW, isn't that the cost of doing the query above far more expensive than
doing a little coding at the application level?
That's
On Wed, Nov 12, 2008 at 3:59 AM, zxo102 ouyang [EMAIL PROTECTED] wrote:
Hi everyone,
My data with same timestamp 2008-11-12 12:12:12 in postgresql are as
follows
rowid data unitchannel create_on
Hi Ho!
--- On Thu, 11/13/08, Brent Wood [EMAIL PROTECTED] wrote:
You need to use a self relation, not a group by, as no data
are being aggregated into a new single value, which is what
the group by achieves.
This joins a table to itself, so that columns in it can be
replicated. The key is
Hi everyone,
My data with same timestamp 2008-11-12 12:12:12 in postgresql are as
follows
rowid data unitchannel create_on
--
11.5 MPa channel1 2008-11-12 12:12:12
2
zxo102 ouyang wrote:
I would like to group them into one line with SQL like
1.5 MPa 2.5M3 3.5 M3 4.5 t 2008-11-12 12:12:12
Look up the GROUP BY clause.
http://www.postgresql.org/docs/current/static/sql-select.html
Note that with timestamps you may have to
You need to use a self relation, not a group by, as no data are being
aggregated into a new single value, which is what the group by achieves.
This joins a table to itself, so that columns in it can be replicated. The key
is that the where clause in each case
needs to just select one channel,
On Thu, Nov 13, 2008 at 06:56:43AM +1300, Brent Wood wrote:
You need to use a self relation, not a group by, as no data are
being aggregated into a new single value, which is what the group by
achieves.
It's perfectly possible to use a GROUP BY clause; all rows from one time
period want to be
