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INNER JOIN vs LEFT JOIN performance in SQL Server
... slower; by definition, an outer join (LEFT JOIN or RIGHT JOIN) has to do all the work of an INNER JOIN plus the extra work of null-extending the results. It would also be expected to return more rows, further increasing the total execution time simply due to the larger size of the result set.
(A...
pip install mysql-python fails with EnvironmentError: mysql_config not found
...
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...
Windows git “warning: LF will be replaced by CRLF”, is that warning tail backward?
...E_CRLF_FAIL */
die("LF would be replaced by CRLF in %s", path);
It is called by convert.c#crlf_to_git(), itself called by convert.c#convert_to_git(), itself called by convert.c#renormalize_buffer().
And that last renormalize_buffer() is only called by merge-recursive.c#blob_unchanged().
So I s...
What is the difference between user variables and system variables?
...eating the environment for an application. System variables are shared for all users, but user variables are only for your account/profile.
If you deleted the system ones by accident, bring up the Registry Editor, then go to HKLM\ControlSet002\Control\Session Manager\Environment (assuming your curr...
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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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...
How do you do block comments in YAML?
...:
The syntax differences are subtle and seldom arise in practice: JSON allows extended charactersets like UTF-32, YAML requires a space after separators like comma, equals, and colon while JSON does not, and some non-standard implementations of JSON extend the grammar to include Javascript's /* ...