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How to create a MySQL hierarchical recursive query
... parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inner join cte
on p.parent_id = cte.id
)
select * from cte;
The value specified in parent_id = 19 should be set to the...
How to export table as CSV with headings on Postgresql?
...
COPY products_273 TO '/tmp/products_199.csv' WITH (FORMAT CSV, HEADER);
as described in the manual.
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...
List comprehension: Returning two (or more) items for each item
...bda x: x + 2
>>> g = lambda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_itera...
What parameters should I use in a Google Maps URL to go to a lat-lon?
...
In May 2017 Google announced the Google Maps URLs API that allows to construct universal cross-platform links. Now you can open Google maps on web, Android or iOS using the same URL string in form:
https://www.google.com/maps/search/?api=1&parameters
There are several modes tha...
Select columns from result set of stored procedure
...
Here's a link to a pretty good document explaining all the different ways to solve your problem (although a lot of them can't be used since you can't modify the existing stored procedure.)
How to Share Data Between Stored Procedures
Gulzar's answer will work (it is document...
Undoing a 'git push'
... highly dangerous if you are working in a shared repo. As a best practice, all commits pushed to a remote repo that is shared should be considered 'immutable'. Use 'git revert' instead: kernel.org/pub/software/scm/git/docs/…
– Saboosh
Jan 13 '12 at 20:47
...
Sound effects in JavaScript / HTML5
...io objects directly:
var snd = new Audio("file.wav"); // buffers automatically when created
snd.play();
There's no support for mixing in current version of the spec.
To play same sound multiple times, create multiple instances of the Audio object. You could also set snd.currentTime=0 on the obj...
How do you dismiss the keyboard when editing a UITextField
... the point. By subscribing to the DidEndOnExit event, you do not need to call resignFirstResponder. You can test this by putting a symbolic breakpoint on [UIResponder resignFirstResponder]. Note that even if if you don't call resignFirstResponder, it still gets called by the system. This is expl...
Github: Can I see the number of downloads for a repo?
...in his (upvoted) answer, does use that field in his python script.
(very small extract)
c.setopt(c.URL, 'https://api.github.com/repos/' + full_name + '/releases')
for p in myobj:
if "assets" in p:
for asset in p['assets']:
print (asset['name'] + ": " + str(asset['download_co...
iphone Core Data Unresolved error while saving
...conflict with the old model implementation.
Edit:
I almost forgot here's all the error codes that Core Data spits out:
Core Data Constants Reference
I had trouble with this before and I realised I unchecked the correct optional box. Such trouble finding out the problem. Good luck.
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