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How to add not null constraint to existing column in MySQL
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Just use an ALTER TABLE... MODIFY... query and add NOT NULL into your existing column definition. For example:
ALTER TABLE Person MODIFY P_Id INT(11) NOT NULL;
A word of caution: you need to specify the full column definition again when using a MODIFY query. If you...
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 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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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(...
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 ...
Ruby optional parameters
...his method: e.g. If you're trying to make the default value for scope true and you pass in false, scope ||= true won't work. It evaluates the same as nil and will set it to true
– Joshua Pinter
Nov 10 '11 at 5:32
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How to find where a method is defined at runtime?
...d occurred, a backend process failed to run. Now, we were good little boys and girls and ran rake test after every check-in but, due to some oddities in Rails' library loading, it only occurred when we ran it directly from Mongrel in production mode.
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Delete terminal history in Linux [closed]
When you use the up key in a Linux terminal, you can use previous commands again. Great feature. However, I started logging mysql into mysql with the sensitive details in the command.
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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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How to create a CPU spike with a bash command
...want to create a near 100% load on a Linux machine. It's quad core system and I want all cores going full speed. Ideally, the CPU load would last a designated amount of time and then stop. I'm hoping there's some trick in bash. I'm thinking some sort of infinite loop.
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