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Is there any difference between GROUP BY and DISTINCT

...ukas Eder 171k105105 gold badges562562 silver badges12371237 bronze badges ...
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Regular expression for letters, numbers and - _

...et to show how you can use this pattern: <?php $arr = array( 'screen123.css', 'screen-new-file.css', 'screen_new.js', 'screen new file.css' ); foreach ($arr as $s) { if (preg_match('/^[\w.-]*$/', $s)) { print "$s is a match\n"; } else { print "$s is NO match!!!\n"; }; } ...
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Unresolved external symbol on static class members

...le looks like: //myClass.cpp void myClass::myFunc() { myClass::m_nMyVar = 123; //I tried to use this m_nMyVar here and got link error } So I add below code on the top of myClass.cpp //myClass.cpp int myClass::m_nMyVar; //it seems redefine m_nMyVar, but it works well void myClass::myFunc() { myCl...
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Understanding :source option of has_one/has_many through of Rails

...'ve chosen to namespace the Dog::Breed, because we want to access Dog.find(123).breeds as a nice and convenient association. Now, if we now want to create a has_many :dog_breeds, :through => :dogs association on Pet, we suddenly have a problem. Rails won't be able to find a :dog_breeds associati...
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Which is the preferred way to concatenate a string in Python?

... to a string, then to a list: a += b: 0.10780501365661621 a.append(b): 0.1123361587524414 OK, turns out that even when the resulting string is a million characters long, appending was still faster. Now let's try with appending a thousand character long string a hundred thousand times: a += b: 0...
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How to use hex color values

... How would you handle 123ABC? The compiler is burking at it not being a digit. – Islam Q. Mar 2 '16 at 6:28 1 ...
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Cast a Double Variable to Decimal

...hould use the M when declaring a new literal decimal value: decimal dec = 123.45M; (Without the M, 123.45 is treated as a double and will not compile.) share | improve this answer | ...
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How to pass an array into a SQL Server stored procedure

...tion for this problem. You should only create an string expression like ';123;434;365;' in-which 123, 434 and 365 are some employeeIDs. By calling the below procedure and passing this expression to it, you can fetch your desired records. Easily you can join the "another table" into this query. This...
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What is a method group in C#?

...) overload which takes a string parameter: Func<string,string> fn = 123.ToString; Console.WriteLine(fn("00000000")); This example picks the ToString() overload which takes no parameters: Func<string> fn = 123.ToString; Console.WriteLine(fn()); ...
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Flatten nested dictionaries, compressing keys

...stance(dd, dict) else { prefix : dd } Test: In [2]: flatten_dict({'abc':123, 'hgf':{'gh':432, 'yu':433}, 'gfd':902, 'xzxzxz':{"432":{'0b0b0b':231}, "43234":1321}}, '.') Out[2]: {'abc': 123, 'gfd': 902, 'hgf.gh': 432, 'hgf.yu': 433, 'xzxzxz.432.0b0b0b': 231, 'xzxzxz.43234': 1321} ...