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How to create a unique index on a NULL column?
I am using SQL Server 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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Do regular expressions from the re module support word boundaries (\b)?
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>>> y = k.search( x)
>>> y
<_sre.SRE_Match object at 0x100418850>
Also forgot to mention, you should be using raw strings in your code
>>> x = 'one two three'
>>> y = re.search(r"\btwo\b", x)
>>> y
<_sre.SRE_Match object at 0x100418a58>
&g...
How do I resize an image using PIL and maintain its aspect ratio?
...8, 128
for infile in sys.argv[1:]:
outfile = os.path.splitext(infile)[0] + ".thumbnail"
if infile != outfile:
try:
im = Image.open(infile)
im.thumbnail(size, Image.ANTIALIAS)
im.save(outfile, "JPEG")
except IOError:
print "cann...
How is std::function implemented?
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80
The implementation of std::function can differ from one implementation to another, but the core ...
vim command to restructure/force text to 80 columns
...tomatically set the width of text in vim using set textwidth (like Vim 80 column layout concerns ). What I am looking for is something similar to = (the indent line command) but to wrap to 80. The use case is sometimes you edit text with textwidth and after joining lines or deleting/adding text...
What does @synchronized() do as a singleton method in objective C?
...dit: Adding some more information that wasn't in the original answer from 2011.
The @synchronized directive prevents multiple threads from entering any region of code that is protected by a @synchronized directive referring to the same object. The object passed to the @synchronized directive is the...
req.query and req.param in ExpressJS
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110
req.query will return a JS object after the query string is parsed.
/user?name=tom&age=55 -...
Change text color based on brightness of the covered background area?
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+50
Interesting resources for this:
W3C - Ensure that foreground and background color combinations provide sufficient contrast
Calculati...
E731 do not assign a lambda expression, use a def
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edited Mar 4 at 17:50
answered Jul 29 '14 at 7:31
Gar...
How can I use if/else in a dictionary comprehension?
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edited Mar 22 at 16:40
Peter Mortensen
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