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What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
...ey are exact representations of the image. Bitmap formats such as BMP generally are uncompressed, although there also are compressed BMP files as well.
Lossy compression formats are generally suited for photographs. It is not suited for illustrations, drawings and text, as compression artifacts fro...
.htaccess - how to force “www.” in a generic way?
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This solution works only if you want all sub-domains forwarded to www.yourdomain.com. If you only want to force www, you should update the second line to be: RewriteCond %{HTTP_HOST} ^yourdomain.com [NC]
– Jared Pomranky
Ma...
Can a foreign key be NULL and/or duplicate?
...at field must exist first in a different table (the parent table). That is all an FK is by definition. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you have a database that stores sales proposals. Suppose furth...
pip install mysql-python fails with EnvironmentError: mysql_config not found
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It seems mysql_config is missing on your system or the installer could not find it.
Be sure mysql_config is really installed.
For example on Debian/Ubuntu you must install the package:
sudo apt-get install libmysqlclient-dev
Maybe the mysql_config is not in your path, it will be ...
Display filename before matching line
... If grep is supplied with multiple file names, it will automatically display the file names before the match, but it will leave the file name out in case of a single input file. By using /dev/null as an extra input file grep "thinks" it dealing with multiple files, but /dev/null is of cou...
Git: add vs push vs commit
...the suggested way to commit is the combined git commit -a, but you can mentally add a git add to the change block to understand the flow.
Lastly, the reason why push is a separate command is because of git's philosophy. git is a distributed versioning system, and your local working directory is your...
Get Output From the logging Module in IPython Notebook
.... The functions debug(), info(), warning(), error() and
critical() will call basicConfig() automatically if no handlers are
defined for the root logger.
This function does nothing if the root logger already has handlers
configured for it.
It seems like ipython notebook call basicConfig ...
Visual Studio: How to break on handled exceptions?
...ad the debug menu, but no Exceptions options. i customized the menu to manually add it; the shortcut key worked either way (Ctrl+Alt+E)
– Ian Boyd
Sep 22 '08 at 19:40
3
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Why are Where and Select outperforming just Select?
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+1 for being the only answer (so far) that actually addresses the question, doesn't guess the answer and doesn't just generate "me too!" statistics.
– Binary Worrier
Aug 20 '13 at 13:21
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Replace whitespaces with tabs in linux
...long options are mandatory for short options
too.
-a, --all
convert all blanks, instead of just initial blanks
--first-only
convert only leading sequences of blanks (overrides -a)
-t, --tabs=N
have tabs N characters apart i...