Instead of doing julianday('now') why not put a text-based timestamp
into whatever object you're queueing up and pass that into the
julianday() function to convert it to a real.On Mon, Sep 22, 2008 at 9:51 AM, P Kishor <[EMAIL PROTECTED]> wrote: > On 9/22/08, jason weaver <[EMAIL PROTECTED]> wrote: >> "jason weaver" <[EMAIL PROTECTED]> wrote: >> news:[EMAIL PROTECTED] >> >> However, due to database locking issues, I need to do a bunch of >> >> inserts in one transaction or batch. Thus, I store them in a simple >> >> queue. Therefore, the julianday('now') won't work because all of my >> >> batch inserts will have the same date and time. And that doesn't >> >> work very well. ;) >> >> >> >From: "Igor Tandetnik" <[EMAIL PROTECTED]> >> >> >You will have to deal with this in any case. E.g. on Windows the system >> >timer resolution is 15ms by default. You can insert quite a few records >> >in 15 ms. >> >It is unrealistic to expect that every record could be inserted with a >> >unique timestamp. Find some other way to ensure uniqueness (e.g. just >> >assign a sequential number to each). >> >> >> >> Thanks for your response. However, my batch inserts and the uniqueness of >> my timestamps aren't the issue. I guess I didn't explain my situation well >> enough. Let me try again. >> >> >> >> I take readings every X seconds which gives me plenty of uniqueness for each >> reading. I save the SQL statements and then insert them in small batches. >> However, from reading this newsgroup I've learned that the correct way to >> put dates into SQLite is as I described before: >> >> >> - create table my_table(date_stuff real); >> >> >> - insert into my_table values(julianday('now')); >> >> >> In my batch loop, I can't use julianday("now") - I need the timestamp >> to reflect when I took the reading. >> >> >> >> If the right way to put datetime in the dbase is the julianday('now') >> format, I need to be able to create and capture that format in python. >> >> >> >> What is the julianday("now") equivalent in python? I can't find a simple, >> straight-forward answer to this question. > > > I have no idea what the julianday("now") equivalent in Python is, but > why not let SQLite do the work? Here is how I would do it with Perl... > (mix of pseudo-code and Perl ahead) > > # prepare statement > $sth = $dbh->prepare(qq{ > INSERT INTO table (somecol, timestamp) > VALUES (?, julianday("now")) > }); > > open transaction... > > # loop through your readings > $sth->execute($somecol); > > end transaction... > > $dbh->commit; > > or throw error... > > The above works for me. > > Keep in mind though... Igor's caveat about not having enough > resolution for timing might apply. So, you might have to use some kind > of high resolution timer. CPAN has one us Perl aficionados... > conveniently, it is called Time::HiRes > <http://search.cpan.org/~jhi/Time-HiRes-1.9715/HiRes.pm> > > I am sure you have one for your Python world as well. If you decide to > use something like that, then you will have to modify your code > accordingly. > >> >> >> >> Thank you, >> >> Chris >> >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users@sqlite.org >> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >> > > > -- > Puneet Kishor http://punkish.eidesis.org/ > Nelson Institute for Environmental Studies http://www.nelson.wisc.edu/ > Open Source Geospatial Foundation (OSGeo) http://www.osgeo.org/ > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
