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Why doesn't String switch statement support a null case?
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According to Java Docs:
A switch works with the byte, short, char, and int primitive data
types. It also works with enumerated types (discussed in Enum Types),
the String class, and a few special classes that wrap certain
primitive types: Character, Byte, Short, and Integer (disc...
Count(*) vs Count(1) - SQL Server
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The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
How do I use the CONCAT function in SQL Server 2008 R2?
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You can use SELECT {fn concat ('foo', 'bar')}; in previous versions. Only accepts 2 parameters though.
– Martin Smith
May 11 '12 at 11:22
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Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...e main method before the QApplication call like this:
int main( int argc, char *argv[] )
{
QCoreApplication::addLibraryPath(".");
QApplication app( argc, argv );
...
return app.exec();
}
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Increment a database field by 1
...complex depending on your specific needs:
INSERT into mytable (logins)
SELECT max(logins) + 1
FROM mytable
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What is Full Text Search vs LIKE
... can enable support for leading wildcards by pre-compiling suffix trees in selected fields.
Other features typical of full-text search are
lexical analysis or tokenization—breaking a
block of unstructured text into
individual words, phrases, and
special tokens
morphological
analysis, or stemmi...
How do you configure an OpenFileDialog to select folders?
In VS .NET, when you are selecting a folder for a project, a dialog that looks like an OpenFileDialog or SaveFileDialog is displayed, but is set up to accept only folders. Ever since I've seen this I've wanted to know how it's done. I am aware of the FolderBrowserDialog, but I've never really like...
How to throw an exception in C?
...);
}catch(int64_t x){
printf("good %ld",x);
}
}
int main(int argc, char *argv[])
{
foo();
return 0;
}
to compile it
gcc -o bar.o -c bar.c && g++ a.cc bar.o && ./a.out
output
good 1976
http://mentorembedded.github.io/cxx-abi/abi-eh.html has more detail info about _...
How to execute raw SQL in Flask-SQLAlchemy app
...xecute("<sql here>")
or:
from sqlalchemy import text
sql = text('select name from penguins')
result = db.engine.execute(sql)
names = [row[0] for row in result]
print names
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How to select a CRAN mirror in R
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Repository selection screen cannot be shown on your system (OS X), since OS X no longer includes X11. R tries to show you the prompt through X11. Install X11 from http://xquartz.macosforge.org/landing/. Then run the install command. The...