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How to get whole and decimal part of a number?
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As a side, intval() or simple casting as (int) might be more performant than floor()
– Jason McCreary
Jul 8 '11 at 2:36
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TSQL - How to use GO inside of a BEGIN .. END block?
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@gbn @mellamokb: I meant statements like SELECT * <newline> FROM whatever. If I execute every line with its own EXEC statement, that will break. Or are you suggesting I break at every GO statement?
– BlueRaja - Danny Pflughoeft
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How to return multiple objects from a Java method?
...pressWarnings("unchecked")
public static <P, Q> Pair<P, Q> cast(Pair<?, ?> pair, Class<P> pClass, Class<Q> qClass) {
if (pair.isInstance(pClass, qClass)) {
return (Pair<P, Q>) pair;
}
throw new ClassCastException();
}...
SQL Data Reader - handling Null column values
...sqlreader[indexAge] as int? ?? default(int);
The as operator handles the casting including the check for DBNull.
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How to check if an object is a certain type
... Is there a performance difference between the two? - What about Select Case (Obj.GetType()) with multiple test cases Vs multiple IF TypeOf Obj is ...?
– Luke T O'Brien
May 22 '17 at 16:27
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What is std::move(), and when should it be used?
...the object has type "rvalue-reference" (Type &&).
std::move() is a cast that produces an rvalue-reference to an object, to enable moving from it.
It's a new C++ way to avoid copies. For example, using a move constructor, a std::vector could just copy its internal pointer to data to the new...
Convert a String In C++ To Upper Case
...like 30x worse than calling glibc's toupper in a loop.) There's a dynamic_cast of the locale that doesn't get hoisted out of the per-char loop. See my answer. On the plus side, this may be properly UTF-8 aware, but the slowdown doesn't come from handling UTF-8; it comes from using a dynamic_cast ...
Populate data table from data reader
... conn = new SqlConnection(connString);
string query = "SELECT * FROM Customers";
SqlCommand cmd = new SqlCommand(query, conn);
conn.Open();
SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
DataTable dtSchema = ...
Possible Loss of Fraction
...two int's into a floating point value the fraction portion is lost. If you cast one of the items to a float, you won't get this error.
So for example turn 10 into a 10.0
double returnValue = (myObject.Value / 10.0);
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$_POST vs. $_SERVER['REQUEST_METHOD'] == 'POST'
...ts regardless if the request was sent with POST headers. An empty array is cast to false in a boolean check.
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