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How do I set a column value to NULL in SQL Server Management Studio?
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I think @Zack properly answered the question but just to cover all the bases:
Update myTable set MyColumn = NULL
This would set the entire column to null as the Question Title asks.
To set a specific row on a specific column to null use:
Update myTable set MyColumn = NULL where Fi...
What is the difference between “Class.forName()” and “Class.forName().newInstance()”?
...demo = (Demo) clazz.newInstance();
}
}
As explained in its javadoc, calling Class.forName(String) returns the Class object associated with the class or interface with the given string name i.e. it returns test.Demo.class which is affected to the clazz variable of type Class.
Then, calling cla...
PHP + MySQL transactions examples
I really haven't found normal example of PHP file where MySQL transactions are being used. Can you show me simple example of that?
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Rails extending ActiveRecord::Base
...the ActiveSupport::Concern documentation for more details.
Create a file called active_record_extension.rb in the lib directory.
require 'active_support/concern'
module ActiveRecordExtension
extend ActiveSupport::Concern
# add your instance methods here
def foo
"foo"
end
# add y...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...the memory pointers are the same. So we know what is going on now. Additionally you can find NSLayoutConstraint in view hierarchy. Since it is selected in View, it selected in Navigator also.
If you need you may also print it on console using address pointer:
(lldb) po 0x17dce920
<UIView: 0x1...
{version} wildcard in MVC4 Bundle
...e have bundles. While defining the bundles we can use wildcards like * for all files in a folder.
3 Answers
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Difference between sh and bash
When writing shell programs, we often use /bin/sh and /bin/bash . I usually use bash , but I don't know what's the difference between them.
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Optimizing away a “while(1);” in C++0x
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Does someone have a good explanation of why this was necessary to allow?
Yes, Hans Boehm provides a rationale for this in N1528: Why undefined behavior for infinite loops?, although this is WG14 document the rationale applies to C++ as well and the document refers to both WG14 and WG21:
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How do I parse a string with a decimal point to a double?
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Well, XmlConvert is not really intended to be used to parse a single double value in code. I prefer to use double.Parse or Convert.ToDouble that make my intention obvious.
– Mehrdad Afshari
Aug 30 '09 at 21:29
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Calc of max, or max of calc in CSS
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min(), max(), and clamp() are finally available!
Starting in Firefox 75, Chrome 79, and Safari 11.1 (except clamp).
min() and max() take any number of arguments.
clamp() has syntax clamp(MIN, VAL, MAX) and is equivalent to max(MIN, min(VAL, MAX)).
min() ...