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Unique constraint on multiple columns
...o I add a unique constraint for columns fcode, scode, dcode with t-sql and/or management studio ? fcode, scode, dcode must be unique together.
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How much faster is C++ than C#?
...++ code. However C++ code used to be significantly faster for a long time, and also today still is in many cases. This is mainly due to the more advanced JIT optimizations being complicated to implement, and the really cool ones are only arriving just now.
So C++ is faster, in many cases. But this ...
What's the difference between => , ()=>, and Unit=>
I'm trying to represent a function that takes no arguments and returns no value (I'm simulating the setTimeout function in JavaScript, if you must know.)
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How to make a window always stay on top in .Net?
...cro in another program. The other program will continually pop up windows and generally make things look, for lack of a better word, crazy. I want to implement a cancel button that will stop the process from running, but I cannot seem to get the window to stay on top. How do I do this in C#?
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What is the “-->” operator in C++?
After reading Hidden Features and Dark Corners of C++/STL on comp.lang.c++.moderated , I was completely surprised that the following snippet compiled and worked in both Visual Studio 2008 and G++ 4.4.
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Place cursor at the end of text in EditText
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@marqss, I had the same issue and worked perfectly for me. I was using EditText on a Dialog and pre-populating text from the main screen. When that happens the cursor was staying at the beginning and not at the end but after I tried your suggestion ever...
Compare two Byte Arrays? (Java)
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You can use both Arrays.equals() and MessageDigest.isEqual(). These two methods have some differences though.
MessageDigest.isEqual() is a time-constant comparison method and Arrays.equals() is non time-constant and it may bring some security issues if you ...
Identity increment is jumping in SQL Server database
...es a cache size of 1,000 when allocating IDENTITY values for an int column and restarting the service can "lose" unused values (The cache size is 10,000 for bigint/numeric).
This is mentioned in the documentation
SQL Server might cache identity values for performance reasons and
some of the ...
How to print out the contents of a vector?
... a supplement to the above iterator solution. If you are using the C++11 standard (or later), then you can use the auto keyword to help the readability:
for (auto i = path.begin(); i != path.end(); ++i)
std::cout << *i << ' ';
But the type of i will be non-const (i.e., the compiler ...
Handling an empty UITableView. Print a friendly message
...at you reloadData you should determine if there your table is empty or not and update the UITableView's backgroundView property with a UIView containing a UILabel or just set it to nil. That's it.
It is of course possible to make UITableView's data source do double duty and return a special "list ...