On Mon, Apr 17, 2017 at 04:36:50PM -0700, Marilyn Davis wrote:
> #!/usr/bin/env python3
> """
> Hello Tutors,
>
> I can't figure out why the FillWithStars() function puts Canopus in the db
> twice.
Good question. And thank you for providing a really well-written,
simple, clear script that we can run unchanged to demonstrate the
problem.
I get the same results as you, and like you, I'm not too sure why. But
I'm leading to suspect the blame lies with sqlite, not your code.
If I take your script and add the following lines between the call to
connection.executescript(...) and connection.executemany(...):
stored_stars = connection.execute("SELECT * FROM BRIGHTEST")
for star in stored_stars:
print(star)
del stored_stars
print('-'*30)
I get this output:
[steve@ando ~]$ python3 why4.py
('Canopus', 'Carina', -0.72, -2.5, 74)
----------------------------------------
('Canopus', 'Carina', -0.72, -2.5, 74)
('Canopus', 'Carina', -0.72, -2.5, 74)
('Arcturus', 'Bootes', -0.04, 0.2, 34)
so it looks to me like the initial call to executescript() correctly
adds Canopus once, and then the call to executemany() mysteriously
duplicates it.
I tried one more iteration: swap the two stars, so that Acturus
is added first, then Canopus:
[steve@ando ~]$ python3 why5.py
('Arcturus', 'Bootes', -0.04, 0.2, 34)
----------------------------------------
('Arcturus', 'Bootes', -0.04, 0.2, 34)
('Arcturus', 'Bootes', -0.04, 0.2, 34)
('Canopus', 'Carina', -0.72, -2.5, 74)
At this point, I'm not sure whether this is a bug in sqlite, or a
misunderstanding that we're doing something wrong. I think this now
needs an sqlite expert.
--
Steve
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