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Why isn't String.Empty a constant?
...y is used instead of const is due to use with unmanaged code, as indicated by Microsoft here in the Shared Source Common Language Infrastructure 2.0 Release. The file to look at is sscli20\clr\src\bcl\system\string.cs.
The Empty constant holds the empty
string value. We need to call the
Stri...
How do I kill all the processes in Mysql “show processlist”?
...
You need to kill them one by one, MySQL does not have any massive kill command. You can script it in any language, for example in PHP you can use something like:
$result = mysql_query("SHOW FULL PROCESSLIST");
while ($row=mysql_fetch_array($result)) ...
String literals and escape characters in postgresql
...e an extension to the SQL standard. An escape string constant is specified by writing the letter E (upper or lower case) just before the opening single quote, e.g. E'foo'. (When continuing an escape string constant across lines, write E only before the first opening quote.) Within an escape string, ...
How can I save an image with PIL?
...hat this is old, but I've found that (while using Pillow) opening the file by using open(fp, 'w') and then saving the file will work. E.g:
with open(fp, 'w') as f:
result.save(f)
fp being the file path, of course.
sha...
Difference between SRC and HREF
... document (in case of link) and the destination anchor or resource defined by this attribute. When we write:
<link href="style.css" rel="stylesheet" />
The browser understands that this resource is a stylesheet and the processing parsing of the page is not paused (rendering might be paused ...
Determine which JAR file a class is from
...
Yes. It works for all classes except classes loaded by bootstrap classloader. The other way to determine is:
Class klass = String.class;
URL location = klass.getResource('/' + klass.getName().replace('.', '/') + ".class");
As notnoop pointed out klass.getResource() method r...
How do you do a ‘Pause’ with PowerShell 2.0?
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/c Carries out the command specified by string and then terminates | out-null pipes the output to out-null, where you'll never see it If you want to see the "Press any key to continue..." message, remove the pipe. Also, this doesn't seem to work in PowerShel...
Statistics: combinations in Python
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A quick search on google code gives (it uses formula from @Mark Byers's answer):
def choose(n, k):
"""
A fast way to calculate binomial coefficients by Andrew Dalke (contrib).
"""
if 0 <= k <= n:
ntok = 1
ktok = 1
for t in xrange(1, min(k, n ...
python location on mac osx
...gt;>>
Items in /usr/bin should always be or link to files supplied by Apple in OS X, unless someone has been ill-advisedly changing things there. To see exactly where the /usr/local/bin/python is linked to:
$ ls -l /usr/local/bin/python
lrwxr-xr-x 1 root wheel 68 Jul 5 10:05 /usr/local...
How do you kill all current connections to a SQL Server 2005 database?
...have another set of DBA credentials before you attempt this. I fixed this by reverting to one of the previous snapshots. Lost some data. Luckily the data wasn't critical.
– RuntimeException
Dec 4 '14 at 15:12
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