query progress bar

[Timothy Smith]

is it possible to mke a progress bar for queries? say i have a query
that will take 20 seconds, i'd like to give some feed back to users on
how long this will take.

[ryan]

What type of UI is this for? The Python Cookbook, 2nd Ed. has a nice
textual solution. I'm not sure if this is the same one, but here is <a
href="http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/168639">one
from ASPN</a>. Here is one <a
href="http://wxpython.org/docs/api/wx.ProgressDialog-class.html"> for
wxPython.</a>

[Timothy Smith]

ry**@ryankaskel.com wrote:

What type of UI is this for? The Python Cookbook, 2nd Ed. has a nice
textual solution. I'm not sure if this is the same one, but here is <a
href="http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/168639">one
from ASPN</a>. Here is one <a
href="http://wxpython.org/docs/api/wx.ProgressDialog-class.html"> for
wxPython.</a>

it's for wx, the problem isn't making the progress bar itself, it's
knowing how long the query is going to run for.
i'm using pypgsql

[Harald Massa]

> it's for wx, the problem isn't making the progress bar itself, it's

knowing how long the query is going to run for.
i'm using pypgsql

It is quite easy:

from timemachine import oracle

guesser=oracle(guess="SQL")
guesser.set_hint(driver="pypgsql")
guesser.set_hint(gui="wx")

expected_runtime=guesser.estimate("<put your query text here>")

Only problem is that the timemachine module is currently only installed
on Guidos and Tims Python.

Harald

[Timothy Smith]

Harald Massa wrote:

it's for wx, the problem isn't making the progress bar itself, it's
knowing how long the query is going to run for.
i'm using pypgsql

It is quite easy:

from timemachine import oracle

guesser=oracle(guess="SQL")
guesser.set_hint(driver="pypgsql")
guesser.set_hint(gui="wx")

expected_runtime=guesser.estimate("<put your query text here>")

Only problem is that the timemachine module is currently only installed
on Guidos and Tims Python.

Harald

man thats exactly what i'm looking for. it won't install on standard 2.3 ?

[f]

Timothy Smith wrote:

is it possible to mke a progress bar for queries? say i have a query
that will take 20 seconds, i'd like to give some feed back to users on
how long this will take.

it is strictly impossible to predict that cause of network load, server
load, query complexity ....

i recommend you put an activity widget, something moving (ie throbber in
wxPython) while waiting for the result (like the rotating circle in
firefox).

once query is finished stop your moving stuff, so the user knows it's
completed.

So you don't need a progress bar, but an activity widget. in gtk, i saw
that progress bar could be put in activity mode.

And don't forget to add a timeout ...

François

[Bernhard Holzmayer]

Timothy Smith wrote:

i'm using pypgsql

Assuming you work with PostgreSQL, then:
You know the EXPLAIN command?

EXPLAIN will give you a very accurate estimation for the expense for the
query.
(You'll have to find out what cost means in terms of your progress.)

I did never try this using pypgsql, but if it works, this might be your
solution...

The precision of EXPLAIN, however, depends on the modifications since the
last time you ran VACUUM on the DB.
If the size of tables or indices didn't suffer considerable changes since
then, the estimation should be quite accurate.

Bernhard

[Timothy Smith]

Bernhard Holzmayer wrote:

Timothy Smith wrote:

i'm using pypgsql

Assuming you work with PostgreSQL, then:
You know the EXPLAIN command?

EXPLAIN will give you a very accurate estimation for the expense for the
query.
(You'll have to find out what cost means in terms of your progress.)

I did never try this using pypgsql, but if it works, this might be your
solution...

The precision of EXPLAIN, however, depends on the modifications since the
last time you ran VACUUM on the DB.
If the size of tables or indices didn't suffer considerable changes since
then, the estimation should be quite accurate.

Bernhard

i've never heard of pypgsql supporting andthing like that, but i'll have
a look

[Scott David Daniels]

f wrote:

Timothy Smith wrote:

is it possible to mke a progress bar for queries? say i have a query
that will take 20 seconds, i'd like to give some feed back to users on
how long this will take.

....an activity widget, something moving (ie throbber in wxPython)
while waiting for the result (like the rotating circle in firefox)....

The one extra thing you might want to do, if your application gets
regular use, is show elapsed time. The user will come to know how
long it should take, while your application probably won't get any
smarter.

--Scott David Daniels
Sc***********@Acm.Org