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How To Change DataType of a DataColumn in a DataTable?
... of the column after the DataTable is filled, you can change it after you call FillSchema, but before you call Fill. For example, say the 3rd column is the one you want to convert from double to Int32, you could use:
adapter.FillSchema(table, SchemaType.Source);
table.Columns[2].DataType = typeof (...
How do I use cascade delete with SQL Server?
...o perform cascading delete in SQL Server when a record from T1 is deleted, all associated records in T2 also deleted.
8 An...
static linking only some libraries
How can I statically link only a some specific libraries to my binary when linking with GCC?
8 Answers
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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
Difference between assertEquals and assertSame in phpunit?
...
I use both sporadically, but according to the docs:
assertSame
Reports an error identified by $message if the two variables $expected and $actual do not have the same type and value."
And as you can see in the example below the above exc...
System.IO.Packaging
...the docs for any of the actual methods/objects/etc. in the namespace, they all say "Assembly: WindowBase.dll"
– dlev
Aug 31 '11 at 16:39
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How to forward declare a template class in namespace std?
...rs. Of course, I know that there are more template params for std::list (allocator I think). But, that is beside the point. Do I have to know the full template declaration of a template class to be able to forward declare it?
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Can I call memcpy() and memmove() with “number of bytes” set to zero?
... the length of the array for a
function, n can have the value zero on a call to that function. Unless explicitly stated
otherwise in the description of a particular function in this subclause, pointer arguments
on such a call shall still have valid values, as described in 7.1.4. On such a call...
Creating a JSON response using Django and Python
...JSON content.
import json
from django.http import HttpResponse
response_data = {}
response_data['result'] = 'error'
response_data['message'] = 'Some error message'
Pre-Django 1.7 you'd return it like this:
return HttpResponse(json.dumps(response_data), content_type="application/json")
For D...
How does C compute sin() and other math functions?
...on in C, contributed by IBM. Since October 2011, this is the code that actually runs when you call sin() on a typical x86-64 Linux system. It is apparently faster than the fsin assembly instruction. Source code: sysdeps/ieee754/dbl-64/s_sin.c, look for __sin (double x).
This code is very complex. N...