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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...y.
Side effects are propagated to replicas too.
correction: both REPLACE and INSERT...ON DUPLICATE KEY UPDATE are non-standard, proprietary inventions specific to MySQL. ANSI SQL 2003 defines a MERGE statement that can solve the same need (and more), but MySQL does not support the MERGE statemen...
How come a non-const reference cannot bind to a temporary object?
...ct,
which function getx() returns? Clearly, this is prohibited by C++ Standard
but I am interested in the purpose of such restriction, not a reference to the standard.
...
What is the best way to check for Internet connectivity using .NET?
What is the fastest and most efficient way to check for Internet connectivity in .NET?
27 Answers
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Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
...SQL views, Hibernate docs write:
There is no difference between a view and a base table for a Hibernate mapping. This is transparent at the database level
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How to remove item from list in C#?
...s {
public int ID; public string FirstName; public string LastName;
}
and assigned some values to results as follows:
var results=new List<myClass> {
new myClass() { ID=1, FirstName="Bill", LastName="Smith" },
new myClass() { ID=2, FirstName="John", LastName="Wilson" },
new ...
Prefer composition over inheritance?
...this case, it makes sense to extract it out as an interface / class / both and make it a member of both classes.
Update: Just came back to my answer and it seems now that it is incomplete without a specific mention of Barbara Liskov's Liskov Substitution Principle as a test for 'Should I be inher...
How to hide first section header in UITableView (grouped style)
...the result is that drawings are no longer aligned to pixels, causing blurs and reducing performance. Just try it in the simulator: it has an option to highlight problematic alignment.
– Codo
Nov 1 '13 at 17:02
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Easy way to write contents of a Java InputStream to an OutputStream
... but I suspect I'm just missing something which would make my life easier (and the code clearer).
23 Answers
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What is an optional value in Swift?
...long with Generics) are one of the most difficult Swift concepts to understand. Because of how they are written and used, it's easy to get a wrong idea of what they are. Compare the optional above to creating a normal String:
var name: String = "Bertie" // No "?" after String
From the syntax it loo...
Why use the SQL Server 2008 geography data type?
...lDegrees = 1
Begin
set @X = 1
END
Else
Begin
set @X = 24
End
-- convert to decimal degrees
set @Lat1 = @Latitude1 * @X
set @Long1 = @Longitude1 * @X
set @Lat2 = @Latitude2 * @X
set @Long2 = @Longitude2 * @X
-- convert to radians: radians = (degrees/180) * PI
set @Lat1 = (@Lat1 / 180) * @...