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Does MySQL ignore null values on unique constraints?
...
Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSER...
Remove or uninstall library previously added : cocoapods
...en by Kyle Fuller - deintegrate, I'll post the proper workflow here:
Install clean:
$ sudo gem install cocoapods-clean
Run deintegrate in the folder of the project:
$ pod deintegrate
Clean:
$ pod clean
Modify your podfile (delete the lines with the pods you don't want to use anymore) and run...
How does the socket API accept() function work?
...r IP : Server Port
So while the Server IP and Server Port are constant in all accepted connections, the client side information is what allows it to keep track of where everything is going.
Example to clarify things:
Say we have a server at 192.168.1.1:80 and two clients, 10.0.0.1 and 10.0.0.2.
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Should the folders in a solution match the namespace?
...the .Core is stripped off" alone. I have a MyProject.Core.dll assembly and all classes begin with MyProject.Core. Stripping off the .Core suffix makes much more sense.
– Luiz Damim
Apr 24 '13 at 23:29
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How to make a SIMPLE C++ Makefile
...o write a simple makefile
What is Make? And Why Should I Care?
The tool called Make is a build dependency manager. That is, it takes care of knowing what commands need to be executed in what order to take your software project from a collection of source files, object files, libraries, headers, et...
How to draw a dotted line with css?
... lot of cruft that is no longer required for modern browsers. I have personally tested the following CSS on all browsers as far back as IE8, and it works perfectly.
hr {
border: none;
border-top: 1px dotted black;
}
border: none must come first, to remove all the default border styling...
How do you roll back (reset) a Git repository to a particular commit? [duplicate]
... to the repository after that point is unimportant to me so I want to omit all subsequent changes from my local source code.
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What is the difference between max-device-width and max-width for mobile web?
... actual device screen
Same goes for max-height and max-device-height naturally.
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How to replace master branch in Git, entirely, from another branch? [duplicate]
...aster
git merge seotweaks
The result should be your master is now essentially seotweaks.
(-s ours is short for --strategy=ours)
From the docs about the 'ours' strategy:
This resolves any number of heads, but the resulting tree of the merge is always that of the current branch head, effecti...
R script line numbers at error?
...ou the line number, but it will tell you where the failure happens in the call stack which is very helpful:
traceback()
[Edit:] When running a script from the command line you will have to skip one or two calls, see traceback() for interactive and non-interactive R sessions
I'm not aware of anot...