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How can I alter a primary key constraint using SQL syntax?
...y constraint name, use query found here to look it up (or look up and drop all at once). http://stackoverflow.com/a/13948609/945875
– Justin
Dec 19 '13 at 20:06
...
How do I set a variable to the output of a command in Bash?
... be done with $(command) or "$(command)", which I find easier to read, and allows for nesting.
OUTPUT=$(ls -1)
echo "${OUTPUT}"
MULTILINE=$(ls \
-1)
echo "${MULTILINE}"
Quoting (") does matter to preserve multi-line variable values; it is optional on the right-hand side of an assignment, as w...
What encoding/code page is cmd.exe using?
...e and other programs
print gibberish, and sometimes they do not.
First of all, Unicode characters will only display if the
current console font contains the characters. So use
a TrueType font like Lucida Console instead of the default Raster Font.
But if the console font doesn’t contain the char...
Rails raw SQL example
...
and then you'd need to call values on this PG::Result object to get the results array
– jobwat
Mar 26 '14 at 1:00
3
...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
Replace all non-alphanumeric characters in a string
...
If you handle unicode a lot, you may also need to keep all non-ASCII unicode symbols: re.sub("[\x00-\x2F\x3A-\x40\x5B-\x60\x7B-\x7F]+", " ", ":%# unicode ΣΘΙП@./\n")
– zhazha
Jul 13 '16 at 7:43
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In Python, how does one catch warnings as if they were exceptions?
...ationWarning)
with warnings.catch_warnings(record=True) as w:
# Cause all warnings to always be triggered.
warnings.simplefilter("always")
# Trigger a warning.
fxn()
# Verify some things
assert len(w) == 1
assert issubclass(w[-1].category, DeprecationWarning)
assert ...
How to remove non-alphanumeric characters?
I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces.
9 Answers
...
BaseException.message deprecated in Python 2.6
...of the exception hierarchy.
Provides an 'args' attribute that contains all arguments passed
to the constructor. Suggested practice, though, is that only a
single string argument be passed to the constructor."""
__str__ and __repr__ are already implemented in a meaningful way,
especiall...
How to fully remove Xcode 4
I want to remove all existing SDK versions as well as Xcode 4.
7 Answers
7
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