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How to drop SQL default constraint without knowing its name?
...ver, I know the query to check if a default constraint exists for a column and drop a default constraint is:
14 Answers
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Generic type conversion FROM string
... store "properties" for another class. These properties simply have a name and a value. Ideally, what I would like is to be able to add typed properties, so that the "value" returned is always of the type that I want it to be.
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How to properly create composite primary keys - MYSQL
... gross oversimplification of an intense setup I am working with. table_1 and table_2 both have auto-increment surrogate primary keys as the ID. info is a table that contains information about both table_1 and table_2 .
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How to exit if a command failed?
I am a noob in shell-scripting. I want to print a message and exit my script if a command fails. I've tried:
8 Answers
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How can I avoid running ActiveRecord callbacks?
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This solution is Rails 2 only.
I just investigated this and I think I have a solution. There are two ActiveRecord private methods that you can use:
update_without_callbacks
create_without_callbacks
You're going to have to use send to call these methods. examples:
p = Person.ne...
How do I disable text selection with CSS or JavaScript? [duplicate]
... edited Jun 1 '15 at 17:08
Andy
1,4461515 silver badges3333 bronze badges
answered Sep 23 '10 at 14:44
Je...
C# generic type constraint for everything nullable
...time check, you can check if the type is not a reference or nullable type, and throw an exception if that's the case.
I realise that only having a runtime check may be unacceptable, but just in case:
public class Foo<T>
{
private T item;
public Foo()
{
var type = typeof(...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...pedef :ed primitive data types is to abstract the low-level representation and make it easier to comprehend ( uint64_t instead of long long type, which is 8 bytes).
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Get JavaScript object from array of objects by value of property [duplicate]
...ction. Otherwise undefined is returned.
Side note: methods like find() and arrow functions are not supported by older browsers (like IE), so if you want to support these browsers, you should transpile your code using Babel.
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Multiple Type Constraints in Swift
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Any way to do the same thing with classes and structs in the type contraint expression? e.g. <T where T:SomeStruct, T:AnotherStruct>? For classes the compiler appears to interpret this as saying "T is a subclass of both", and for structs it just complains that ...