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Importance of varchar length in MySQL table
...s are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
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How to have comments in IntelliSense for function in Visual Studio?
In Visual Studio and C#, when using a built in function such as ToString(), IntelliSense shows a yellow box explaining what it does.
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Using union and order by clause in mysql
...organize.
But this way has the advantage of being fast, not introducing extra variables, and making it easy to separate out each query including the sort. The ability to add a limit is simply an extra bonus.
And of course feel free to turn the union all into a union and add a sort for the whole...
Passing argument to alias in bash [duplicate]
...
An alias will expand to the string it represents. Anything after the alias will appear after its expansion without needing to be or able to be passed as explicit arguments (e.g. $1).
$ alias foo='/path/to/bar'
$ foo some args
will get expanded to
$ ...
Insert code into the page context using a content script
...n('\n');
Method 2b: Using a function
For a big chunk of code, quoting the string is not feasible. Instead of using an array, a function can be used, and stringified:
var actualCode = '(' + function() {
// All code is executed in a local scope.
// For example, the following does NOT overwrit...
Disabling swap files creation in vim
...ing which is a large part of vim use for a lot of people, it seems like an extra bookeeping job better left out. I personally prefer for all jobs to just have no swaps or other auto-backups. If I really need to develop something, I'd rather have a more high level framework to protect me, preferably ...
Difference between HashMap, LinkedHashMap and TreeMap
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private TreeMap<String ,Integer> mySection2 = new TreeMap<>(); mySection2.put("abc1", 2); mySection2.put("abc2",5); mySection2.put("abc3",3); ...
When should you use 'friend' in C++?
... access the private parts of class Child.
friend class Mother;
public:
string name( void );
protected:
void setName( string newName );
};
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Determine the data types of a data frame's columns
...integer" "logical" "factor"
Using str() gets you that information plus extra goodies (such as the levels of your factors and the first few values of each variable):
str(my.data)
'data.frame': 5 obs. of 4 variables:
$ y : num 1.03 1.599 -0.818 0.872 -2.682
$ x1: int 1 2 3 4 5
$ x2: logi T...
No submodule mapping found in .gitmodule for a path that's not a submodule
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in the file .gitmodules, I replaced string
"path = thirdsrc\boost"
with
"path = thirdsrc/boost",
and it solved! - -
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