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If table exists drop table then create it, if it does not exist just create it

...s case than not to cover, see locking note below). Second RENAME ... atomically replaces table definition, refer to MySQL manual for details. At last, DROP ... just cleans up the old table, obviously. Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...
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What's the difference between :: (double colon) and -> (arrow) in PHP?

... used to access static members, such usage is discouraged), while :: is usually used to access static members (though in a few special cases, it's used to access instance members). In general, :: is used for scope resolution, and it may have either a class name, parent, self, or (in PHP 5.3) static...
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Convert all first letter to upper case, rest lower for each word

... Haha, really? That's where it is? I love .NET but some of the API designers are real jerks. – George Mauer Dec 21 '09 at 23:37 ...
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Difference between shared objects (.so), static libraries (.a), and DLL's (.so)?

... and shared objects are just different terms for the same thing - Windows calls them DLLs, while on UNIX systems they're shared objects, with the general term - dynamically linked library - covering both (even the function to open a .so on UNIX is called dlopen() after 'dynamic library'). They are ...
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How to determine the version of the C++ standard used by the compiler?

... By my knowledge there is no overall way to do this. If you look at the headers of cross platform/multiple compiler supporting libraries you'll always find a lot of defines that use compiler specific constructs to determine such things: /*Define Microsoft V...
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What does the Q_OBJECT macro do? Why do all Qt objects need this macro?

I just started using Qt and noticed that all the example class definitions have the macro Q_OBJECT as the first line. What is the purpose of this preprocessor macro? ...
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How can I transform between the two styles of public key format, one “BEGIN RSA PUBLIC KEY”, the oth

...s of two numbers: the modulus (e.g. a 2,048 bit number) the exponent (usually 65,537) Using your RSA public key as an example, the two numbers are: Modulus: 297,056,429,939,040,947,991,047,334,197,581,225,628,107,021,573,849,359,042,679,698,093,131,908,015,712,695,688,944,173,317,630,555,849,7...
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Django - filtering on foreign key properties

... You can add a .query.as_sql() to see what sql will actually be executed. – fastmultiplication Jul 17 '10 at 5:19 ...
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How to import multiple .csv files at once?

...ariables but each from different times. Is there a way in R to import them all simultaneously rather than having to import them all individually? ...
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SQLAlchemy IN clause

...w about session.query(MyUserClass).filter(MyUserClass.id.in_((123,456))).all() edit: Without the ORM, it would be session.execute( select( [MyUserTable.c.id, MyUserTable.c.name], MyUserTable.c.id.in_((123, 456)) ) ).fetchall() select() takes two parameters, the first...