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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...
Select columns from result set of stored procedure
I have a stored procedure that returns 80 columns, and 300 rows. I want to write a select that gets 2 of those columns. Something like
...
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 ...
Why does Twitter Bootstrap Use Pixels for Font Size?
...github.com/ivayloc/twbs-rem-em there is no need to make any calculation to convert pixels in rem or em units, there is build in @mixins for this - @include rem(property, values) - also fallback to px and for em convertion you can use em(value).
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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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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.
...
How do I measure time elapsed in Java? [duplicate]
...- starts;
}
public long time(TimeUnit unit) {
return unit.convert(time(), TimeUnit.MILLISECONDS);
}
}
Usage:
TimeWatch watch = TimeWatch.start();
// do something
long passedTimeInMs = watch.time();
long passedTimeInSeconds = watch.time(TimeUnit.SECONDS);
Aft...
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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improve this answer
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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...
Quickly reading very large tables as dataframes
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@skan the end object is a data frame. So you have to convert it to a zoo object in order to use it with zoo. Look at the examples in the zoo docs for illustrations.
– JD Long
Apr 2 '13 at 12:48
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