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Most efficient T-SQL way to pad a varchar on the left to a certain length?
...cely. It will also perform the conversion for you:
declare @n as int = 2
select FORMAT(@n, 'd10') as padWithZeros
Update:
I wanted to test the actual efficiency of the FORMAT function myself. I was quite surprised to find the efficiency was not very good compared to the original answer from Al...
Troubleshooting “Illegal mix of collations” error in mysql
Am getting the below error when trying to do a select through a stored procedure in MySQL.
16 Answers
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What is the difference between == and Equals() for primitives in C#?
... accepts the same type.
If you write age.Equals(newAge), the compiler will select int.Equals(int) as the best overload and implicitly convert short to int. It will then return true, since this method simply compares the ints directly.
short also has a short.Equals(short) method, but int cannot be im...
Java Class.cast() vs. cast operator
Having being taught during my C++ days about evils of the C-style cast operator I was pleased at first to find that in Java 5 java.lang.Class had acquired a cast method.
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How can I cast int to enum?
How can an int be cast to an enum in C#?
31 Answers
31
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Type Checking: typeof, GetType, or is?
...type at execution time. There are rarely any cases to use is as it does a cast and, in most cases, you end up casting the variable anyway.
There is a fourth option that you haven't considered (especially if you are going to cast an object to the type you find as well); that is to use as.
Foo foo ...
How do I convert a double into a string in C++?
...
The boost (tm) way:
std::string str = boost::lexical_cast<std::string>(dbl);
The Standard C++ way:
std::ostringstream strs;
strs << dbl;
std::string str = strs.str();
Note: Don't forget #include <sstream>
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How to convert from System.Enum to base integer?
...g any System.Enum derived type to its corresponding integer value, without casting and preferably without parsing a string.
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How to avoid the “divide by zero” error in SQL?
...rder to avoid a "Division by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/"...
c# why can't a nullable int be assigned null as a value [duplicate]
... null cannot be implicitly converted to int nor vice-versus, so an explict cast is necessary. Try this instead:
int? accom = (accomStr == "noval" ? (int?)null : Convert.ToInt32(accomStr));
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