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How to check if a model has a certain column/attribute?
I have a method that needs to loop through a hash and check if each key exists in a models table, otherwise it will delete the key/value.
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What linux shell command returns a part of a string? [duplicate]
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If you are looking for a shell utility to do something like that, you can use the cut command.
To take your example, try:
echo "abcdefg" | cut -c3-5
which yields
cde
Where -cN-M tells the cut command to return columns ...
How do I remove a single file from the staging area (undo git add)?
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If I understand the question correctly, you simply want to "undo" the git add that was done for that file.
If you need to remove a single file from the staging area, use
git reset HEAD -- <file>
If you need to remove...
How to call any method asynchronously in c#
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If you use action.BeginInvoke(), you have to call EndInvoke somewhere - else the framework has to hold the result of the async call on the heap, resulting in a memory leak.
If you don't want to jump to C# 5 with the async/aw...
How do I get SUM function in MySQL to return '0' if no values are found?
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Isn't SELECT SUM(IFNULL(column,0)) FROM table GROUP BY something more correct? What if we have some IS NULL values and some real values in "column"?
– DarkSide
Nov 11 '13 at 15:03
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Xcode 5 & Asset Catalog: How to reference the LaunchImage?
... = self.view.bounds.size;
NSString* viewOrientation = @"Portrait";
if (UIDeviceOrientationIsLandscape(orientation)) {
viewSize = CGSizeMake(viewSize.height, viewSize.width);
viewOrientation = @"Landscape";
}
NSArray* imagesDict = [[[NSBundle mainBundle] infoDictionar...
MySQL dump by query
...able" -u myuser -pxxxxxxxxx mydatabase
you can redirect it out to a file if you want :
mysql -e "select * from myTable" -u myuser -pxxxxxxxx mydatabase > mydumpfile.txt
Update:
Original post asked if he could dump from the database by query. What he asked and what he meant were different. H...
Class with single method — best approach?
...ge the method contents as needed. As it's a static method, we can't. Sure, if we just need to add functionality either before or after the old method, we can create a new class and call the old one inside of it - but that's just gross.
Interface woes
Static methods cannot be defined through interfa...
How does HashSet compare elements for equality?
...qualityComparer<T> (EqualityComparer<T>.Default unless you specify a different one on construction).
When you add an element to the set, it will find the hash code using IEqualityComparer<T>.GetHashCode, and store both the hash code and the element (after checking whether the elem...
In WPF, what are the differences between the x:Name and Name attributes?
...is set (not x:Name) when you edit the XAML via the designer. It appears as if MS encourages the use of Name over x:Name so I guess that is the defacto standard.
– Nebula
Feb 27 '13 at 9:15
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