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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... NULL is less efficient
In PostgreSQL, NOT IN is less efficient
In Oracle, all three methods are the same.
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How to find memory leak in a C++ code/project?
...e software tools
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Understand the operator basics. The C++ operator new allocates heap memory. The delete operator frees heap memory. For every new, you should use a delete so that you free the same memory you allocated:
char* str = new char [30]; // Allocate 30 bytes to house a string.
delete ...
What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
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General numeric sort compares the numbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.o...
Checkout remote branch using git svn
... svn show-ignore >> .git/info/exclude
You should now be able to see all the Subversion branches on the git side:
git branch -r
Say the name of the branch in Subversion is waldo. On the git side, you'd run
git checkout -b waldo-svn remotes/waldo
The -svn suffix is to avoid warnings of the ...
Where is the 'tests output pane'?
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The message really should be this
Unexpected error detected. Check the Output Window for details which can be found in the Show output from: section. Then select the Tests drop down to read the actual error.
For it is in the output windo...
What is meant by “managed” vs “unmanaged” resources in .NET?
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The term "unmanaged resource" is usually used to describe something not directly under the control of the garbage collector. For example, if you open a connection to a database server this will use resources on the server (for maintaining the connection) and po...
MySQL 'create schema' and 'create database' - Is there any difference
... CREATE SCHEMA is a synonym for CREATE DATABASE as of MySQL 5.0.2.
this all goes back to an ANSI standard for SQL in the mid-80s.
That standard had a "CREATE SCHEMA" command, and it served to introduce
multiple name spaces for table and view names. All tables and views were
created within a "s...
rotating axis labels in R
In R, how do I make a (bar)plot's y axis labels parallel to the X axis instead of parallel to the Y axis?
5 Answers
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When tracing out variables in the console, How to create a new line?
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In ES6/ES2015 you can use string literal syntax called template literals. Template strings use backtick character instead of single quote ' or double quote marks ". They also preserve new line and tab
const roleName = 'test1';
const role_ID = 'test2';
const modal_ID ...
How can I remove an entry in global configuration with git config?
...of --edit), this command will not work but you can do git config --replace-all core.excludesfile "your_value"
– Juan Saravia
Jan 30 '15 at 12:04
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