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Flask-SQLAlchemy how to delete all rows in a single table
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Try delete:
models.User.query.delete()
From the docs: Returns the number of rows deleted, excluding any cascades.
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When to use thread pool in C#? [closed]
... need to make your IO related tasks concurrently such as downloading stuff from remote servers or disk access, but need to do this say once every few minutes, then make your own threads and kill them once you're finished.
Edit: About some considerations, I use thread pools for database access, phys...
How to use glob() to find files recursively?
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pathlib.Path.rglob
Use pathlib.Path.rglob from the the pathlib module, which was introduced in Python 3.5.
from pathlib import Path
for path in Path('src').rglob('*.c'):
print(path.name)
If you don't want to use pathlib, use can use glob.glob('**/*.c'), but don...
Is it a good practice to place C++ definitions in header files?
...umental waste of time (and is not the case for libraries that don't change from compile to compile). When you split things between header/source and better yet, use forward declarations to reduce includes, you can save hours of recompiling when added up across a day.
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Unusual shape of a textarea?
...lick the 'Relaunch Now' button at the bottom of the
browser window.
from: http://html.adobe.com/webplatform/enable/
.container {
overflow: hidden;
shape-inside: polygon(200.67px 198.00px, 35.33px 198.47px, 34.67px 362.47px, 537.00px 362.74px, 535.67px 196.87px, 388.33px 197.00p...
How to read json file into java with simple JSON library
...refore, your parser will return a JSONArray. You can then get JSONObjects from the array ...
JSONArray a = (JSONArray) parser.parse(new FileReader("c:\\exer4-courses.json"));
for (Object o : a)
{
JSONObject person = (JSONObject) o;
String name = (String) person.get("name");
Sys...
How to change Vagrant 'default' machine name?
Where does the name 'default' come from when launching a vagrant box?
7 Answers
7
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What does bundle exec rake mean?
... command to execute a script in the context of the current bundle (the one from your directory's Gemfile). rake db:migrate is the script where db is the namespace and migrate is the task name defined.
So bundle exec rake db:migrate executes the rake script with the command db:migrate in the context...
Why does volatile exist?
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volatile is needed if you are reading from a spot in memory that, say, a completely separate process/device/whatever may write to.
I used to work with dual-port ram in a multiprocessor system in straight C. We used a hardware managed 16 bit value as a semaphore ...
What is the purpose of the single underscore “_” variable in Python?
...a correct username")).
# the usage of underscore in translation comes from examples in the doc
# that have been copy/pasted over decades, like this one:
import gettext
gettext.bindtextdomain('myapplication', '/path/to/my/language/directory')
gettext.textdomain('myapplication')
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