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How to add “on delete cascade” constraints?
... You have to drop the constraint first, then add the correct version. In standard SQL, I believe the easiest way to do this is to
start a transaction,
drop the foreign key,
add a foreign key with on delete cascade, and finally
commit the transaction
Repeat for each foreign key you want to change...
Does it make sense to do “try-finally” without “catch”?
... resources to be cleaned up appropriately. Below is a concrete example of handling the exception from a calling method.
public void yourOtherMethod() {
try {
yourMethod();
} catch (YourException ex) {
// handle exception
}
}
public void yourMethod() throws YourExcep...
Differences between git pull origin master & git pull origin/master
What is the difference between git pull origin master and git pull origin/master ?
3 Answers
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Does it make any sense to use inline keyword with templates?
Since templates are defined within headers and compiler is able to determine if inlining a function is advantageous, does it make any sense? I've heard that modern compilers know better when to inline a function and are ignoring inline hint.
...
Optimal settings for exporting SVGs for the web from Illustrator?
...
SVG profiles
SVG 1.0: all modern desktop and mobile browsers support SVG 1.1, so never choose this option.
SVG 1.1: You will almost always want this.
SVG Tiny/Basic: this is a subset of SVG intended for mobile devices. Only a handful of devices support SVG Tiny and ...
Order data frame rows according to vector with specific order
...work as long as your target contains exactly the same elements as df$name, and neither contain duplicate values.
From ?match:
match returns a vector of the positions of (first) matches of its first argument
in its second.
Therefore match finds the row numbers that matches target's elements, and...
What arguments are passed into AsyncTask?
I don't understand what I am supposed to put in here and where these arguments end up? What exactly should I put, and where exactly will it go? Do I need to include all 3 or can I include 1,2,20?
...
Pandas every nth row
...d use iloc, which takes a row/column slice, both based on integer position and following normal python syntax.
df.iloc[::5, :]
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Difference between hard wrap and soft wrap?
... for the text to be re-flowed into a nice paragraph if you come back later and edit/add/remove words later on. (You can do this manually in emacs with M-q.)
This is rather annoying, since obsessive compulsive people like me then go back and have to manually re-insert the hard breaks at the appropr...
How to get pixel data from a UIImage (Cocoa Touch) or CGImage (Core Graphics)?
...outline, cleaned-up the typos, generalized it to return an array of colors and got the whole thing to compile. Here is the result:
+ (NSArray*)getRGBAsFromImage:(UIImage*)image atX:(int)x andY:(int)y count:(int)count
{
NSMutableArray *result = [NSMutableArray arrayWithCapacity:count];
// ...
