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Simulating group_concat MySQL function in Microsoft SQL Server 2005?
... This example worked for me, but I tried doing another aggregation and it didn't work, gave me an error: "the correlation name 'pre_trimmed' is specified multiple times in a FROM clause."
– PhilChuang
Jan 22 '10 at 19:24
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What's the best way to use R scripts on the command line (terminal)?
It's very convenient to have R scripts for doing simple plots from the command line. However, running R from bash scripts is not convenient at all. The ideal might be something like
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Converting string from snake_case to CamelCase in Ruby
...ssify returns a string, whereas #constantize looks up constant in context (and does need camelize). 'active_record'.constantize gives error, 'active_record'.camelize.constantize returns the constant ActiveRecord, 'active_record'.classify returns the string 'ActiveRecord'. And if you did 'no_class'.c...
onActivityResult is not being called in Fragment
...ityResult(), but it did not make a call to super.onActivityResult() for unhandled result codes. Apparently, even though the fragment is the one making the startActivityForResult() call, the activity gets the first shot at handling the result. This makes sense when you consider the modularity of frag...
How do I rename an open file in Emacs?
...e: http://steve.yegge.googlepages.com/my-dot-emacs-file
(defun rename-file-and-buffer (new-name)
"Renames both current buffer and file it's visiting to NEW-NAME."
(interactive "sNew name: ")
(let ((name (buffer-name))
(filename (buffer-file-name)))
(if (not filename)
(messa...
What is ActiveMQ used for - can we apply messaging concept using a Database?
I looked it up and it used to send messages between 2 systems.
But why? Why wouldn't you just use a Database ?
There must be some feature that ActiveMQ has that Databases do not?
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Duplicate log output when using Python logging module
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The problem is that every time you call myLogger(), it's adding another handler to the instance, which causes the duplicate logs.
Perhaps something like this?
import os
import time
import datetime
import logging
loggers = {}
def myLogger(name):
global loggers
if loggers.get(name):
...
HTTP vs HTTPS performance
Are there any major differences in performance between http and https? I seem to recall reading that HTTPS can be a fifth as fast as HTTP. Is this valid with the current generation webservers/browsers? If so, are there any whitepapers to support it?
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How do I put variables inside javascript strings?
...e('hello %s, how are you doing', my_name);
This is only a simple example and does not take into account different kinds of data types (like %i, etc) or escaping of %s. But I hope it gives you some idea. I'm pretty sure there are also libraries out there which provide a function like this.
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C++ deprecated conversion from string constant to 'char*'
...e following:
char* pointer_to_nonconst = "string literal";
Why? Well, C and C++ differ in the type of the string literal. In C the type is array of char and in C++ it is constant array of char. In any case, you are not allowed to change the characters of the string literal, so the const in C++ is...