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Return Boolean Value on SQL Select Statement
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What you have there will return no row at all if the user doesn't exist. Here's what you need:
SELECT CASE WHEN EXISTS (
SELECT *
FROM [User]
WHERE UserID = 20070022
)
THEN CAST(1 AS BIT)
ELSE CAST(0 AS BIT) END
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Entity Framework vs LINQ to SQL
... (ADO.Net Entity Framework) is an ORM (Object Relational Mapper) API which allows for a broad definition of object domain models and their relationships to many different ADO.Net data providers. As such, you can mix and match a number of different database vendors, application servers or protocols ...
Why does Java's hashCode() in String use 31 as a multiplier?
... i == (i << 5) - i. Modern VMs do this sort of optimization automatically.
(from Chapter 3, Item 9: Always override hashcode when you override equals, page 48)
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java.nio.file.Path for a classpath resource
...t I'd get from Class.getResource(String) ) as a java.nio.file.Path ? Ideally, I'd like to use the fancy new Path APIs with classpath resources.
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Is Fortran easier to optimize than C for heavy calculations?
... that Fortran is or can be faster then C for heavy calculations. Is that really true? I must admit that I hardly know Fortran, but the Fortran code I have seen so far did not show that the language has features that C doesn't have.
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Error on renaming database in SQL Server 2008 R2
... is WITH ROLLBACK IMMEDIATE necessary. If I don't use it at all, will it cause problems?
– user13892
Sep 6 '19 at 17:53
1
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Text border using css (border around text)
...e CSS3 text-shadow :
text-shadow: 0 0 2px #fff;
However it wont show in all browsers right away. Using a script library like Modernizr will help getting it right in most browsers though.
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Does Parallel.ForEach limit the number of active threads?
...on't start 1000 threads - yes, it will limit how many threads are used. Parallel Extensions uses an appropriate number of cores, based on how many you physically have and how many are already busy. It allocates work for each core and then uses a technique called work stealing to let each thread proc...
Inheriting constructors
...explicit A(int x) {}
};
class B: public A
{
using A::A;
};
This is all or nothing - you cannot inherit only some constructors, if you write this, you inherit all of them. To inherit only selected ones you need to write the individual constructors manually and call the base constructor as nee...
Which machine learning classifier to choose, in general? [closed]
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First of all, you need to identify your problem. It depends upon what kind of data you have and what your desired task is.
If you are Predicting Category :
You have Labeled Data
You need to follow Classification A...