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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 = ...
How do I initialize a TypeScript object with a JSON object
I receive a JSON object from an AJAX call to a REST server. This object has property names that match my TypeScript class (this is a follow-on to this question ).
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How to resize the AVD emulator (in Eclipse)?
...ipse:
Go to Window > Android SDK and AVD Manager > Virtual Devices
Select the AVD you want to launch and click Start
Check the Scale display to real size button
Enter how big you want it to appear in inches and press Launch. For this to work, you'll have to also enter a reasonable approxima...
MSTest copy file to test run folder
...ile in Visual Studio, right click on the Solution and choose New Item, and select the TestSettings template. To use the TestSettings file at the command prompt of mstest.exe add the option, /testsettings:C:\Src\mySolution\myProject\local.testsettings (or add as an extra command line option in Team...
Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
.....] Boolean values behave like the values 0 and 1, respectively, in almost all contexts, the exception being that when converted to a string, the strings "False" or "True" are returned, respectively.
There is also, for Python 2:
In numeric contexts (for example when used as the argument to an ...
How can I define a composite primary key in SQL?
...for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from th...
Does using “new” on a struct allocate it on the heap or stack?
...hen you create an instance of a class with the new operator, memory gets allocated on the heap. When you create an instance of a struct with the new operator where does the memory get allocated, on the heap or on the stack ?
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Is there a difference between “==” and “is”?
... a
True
In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work:
>>> 1000 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" i...
Is this object-lifetime-extending-closure a C# compiler bug?
...L_000e: ldloc.0
IL_000f: ldc.r8 42
IL_0018: ldc.r8 1
IL_0021: call float64 [mscorlib]System.Math::Pow(float64, float64)
IL_0026: stfld float64 ConsoleApplication1.Program/Foo/'<>c__DisplayClass1'::capturedVariable
IL_002b: ldarg.0
IL_002c: ldloc.0
IL_002d: ldftn ins...
How to succinctly write a formula with many variables from a data frame?
...kage leaps and in particular the function regsubsets()
functions for model selection. As stated in the documentation:
Model selection by exhaustive search, forward or backward stepwise, or sequential replacement
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