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How to dynamically compose an OR query filter in Django?
...o:
list = [1, 2, 3]
# it gets a bit more complicated if we want to dynamically build
# OR queries with dynamic/unknown db field keys, let's say with a list
# of db fields that can change like the following
# list_with_strings = ['dbfield1', 'dbfield2', 'dbfield3']
# init our q objects variable to ...
Why does sys.exit() not exit when called inside a thread in Python?
...and I'm confused as to why the following code snippet would not exit when called in the thread, but would exit when called in the main thread.
...
Where are $_SESSION variables stored?
...ariable storage is determined by PHP's session.save_path configuration. Usually this is /tmp on a Linux/Unix system. Use the phpinfo() function to view your particular settings if not 100% sure by creating a file with this content in the DocumentRoot of your domain:
<?php
phpinfo();
?>
...
How can I cast int to enum?
... (e.g. "2342342" -- assuming that's not a value of your enum), it will actually allow that without throwing an error! Your enum will have that value (2342342) even though it's not a valid choice in the enum itself.
– JoeCool
Jun 25 '13 at 15:14
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Can anyone explain python's relative imports?
...
Thanks, but this honestly seems really silly. For such a beautiful language, I can't believe the designers would create such a restriction. Isn't there any other way?
– carl
Dec 16 '09 at 23:48
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Maven build failed: “Unable to locate the Javac Compiler in: jre or jdk issue”
...s:
Add and set the JRE in menu Window → Preferences... → Java → Installed JREs:
JRE type: Standard VM JRE
Name: jdk1.6.0_18
JRE home directory: C:\Program Files (x86)\Java\jdk1.6.0_18
If this is not the case, it's possible that the brackets and spaces in the JAVA_HOME path are causing issu...
Learning Python from Ruby; Differences and Similarities
...
[x*x for x in values if x > 15]
to get a new list of the squares of all values greater than 15. In Ruby, you'd have to write the following:
values.select {|v| v > 15}.map {|v| v * v}
The Ruby code doesn't feel as compact. It's also not as efficient since it first converts the values a...
Efficient way to apply multiple filters to pandas DataFrame or Series
...s to apply several filters to a Pandas DataFrame or Series object. Essentially, I want to efficiently chain a bunch of filtering (comparison operations) together that are specified at run-time by the user.
...
What is the use of static constructors?
...required configuration data into readonly fields, etc.
It is run automatically by the runtime the first time it is needed (the exact rules there are complicated (see "beforefieldinit"), and changed subtly between CLR2 and CLR4). Unless you abuse reflection, it is guaranteed to run at most once (eve...
How do you manage databases in development, test, and production?
...of good options. I wouldn't use the "restore a backup" strategy.
Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version.
Use a migr...