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How to add new column to MYSQL table?
...
your table:
q1 | q2 | q3 | q4 | q5
you can also do
ALTER TABLE yourtable ADD q6 VARCHAR( 255 ) after q5
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Why can't R's ifelse statements return vectors?
...tors, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a common con...
Sort Dictionary by keys
...
let dictionary = [
"A" : [1, 2],
"Z" : [3, 4],
"D" : [5, 6]
]
let sortedKeys = Array(dictionary.keys).sorted(<) // ["A", "D", "Z"]
EDIT:
The sorted array from the above code contains keys only, while values have to be retrieved from the original dictiona...
Percentage width child element in absolutely positioned parent on Internet Explorer 7
...u are looking for. The following code displays exactly the same in Firefox 3 (mac) and IE7.
#absdiv {
position: absolute;
left: 100px;
top: 100px;
width: 80%;
height: 60%;
background: #999;
}
#pctchild {
width: 60%;
height: 40%;
background: #CCC;
}
#reldiv {
position...
How to convert a number to string and vice versa in C++
...fy a base, for digits larger than 9, the alphabet is assumed (a=10 until z=35). You can find more information about the exact formatting that can parsed here for floating-point numbers, signed integers and unsigned integers.
Finally, for each function there is also an overload that accepts a std::w...
Retrieve the maximum length of a VARCHAR column in SQL Server
...oy Scheffers
2,8141010 gold badges2424 silver badges3131 bronze badges
answered Mar 6 '12 at 21:35
aweisaweis
4,33433 gold badges2...
How to dismiss keyboard iOS programmatically when pressing return
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answered Sep 12 '13 at 4:55
Nitin GohelNitin Gohel
48.1k1717 gold badges102102 silver badges137137 bronze badges
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How can I list all collections in the MongoDB shell?
...e:
$ mongo prodmongo/app --eval "show collections"
MongoDB shell version: 3.2.10
connecting to: prodmongo/app
2016-10-26T19:34:34.886-0400 E QUERY [thread1] SyntaxError: missing ; before statement @(shell eval):1:5
$ mongo prodmongo/app --eval "db.getCollectionNames()"
MongoDB shell version: 3....
Convert NSArray to NSString in Objective-C
I am wondering how to convert an NSArray [@"Apple", @"Pear ", 323, @"Orange"] to a string in Objective-C .
9 Answers
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Kill child process when parent process is killed
...lic Int64 PerJobUserTimeLimit;
public Int16 LimitFlags;
public UInt32 MinimumWorkingSetSize;
public UInt32 MaximumWorkingSetSize;
public Int16 ActiveProcessLimit;
public Int64 Affinity;
public Int16 PriorityClass;
public Int16 SchedulingClass;
}
[StructLayout(LayoutKind....