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Delete all Duplicate Rows except for One in MySQL? [duplicate]
...n your connection for a large table.
NB - You need to do this first on a test copy of your table!
When I did it, I found that unless I also included AND n1.id <> n2.id, it deleted every row in the table.
If you want to keep the row with the lowest id value:
DELETE n1 FROM names n1, nam...
Why do I need 'b' to encode a string with Base64?
...are only two or 4 bits in the last chunk.
Example:
>>> data = b'test'
>>> for byte in data:
... print(format(byte, '08b'), end=" ")
...
01110100 01100101 01110011 01110100
>>>
If you interpret that binary data as a single integer, then this is how you would convert...
Detect if an element is visible with jQuery [duplicate]
...r to use jQuery considering you're using it in other places anyway:
if($('#testElement').is(':visible')) {
// Code
}
It is important to note that if any one of a target element's parent elements are hidden, then .is(':visible') on the child will return false (which makes sense).
jQuery 3
:visib...
What is the real overhead of try/catch in C#?
...!_user.Rights.Contains(rightName))
throw new Exception();
}
When the test database got fuller with test data, this lead to a very visible slowdown while openening new forms etc.
So I refactored it to the following, which - according to later quick 'n dirty measurements - is about 2 orders of ...
Git command to display HEAD commit id?
...f5ad6286e176fc (tag: v1.0) second
52c1cdcb1988d638ec9e05a291e137912b56b3af test
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Which iomanip manipulators are 'sticky'?
...o the stream. Unfortunately this does not preclude them from being sticky. Tests indicate that all of them except setw are sticky.
setiosflags: Sticky
resetiosflags:Sticky
setbase: Sticky
setfill: Sticky
setprecision: Sticky
All the other manipulators return a stream object. Thus any s...
What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
...nefits: Very complete numeric library. Very, very fast (supposedly the fastest solver). By far the largest, most complete mathematical API. Commercially supported, mature, and stable.
Downsides: Cost - not inexpensive. Very few geometric/rendering specific methods, so you'll need to roll your o...
HtmlEncode from Class Library
...ill need to add the reference to the DLL if it isn't there already
string TestString = "This is a <Test String>.";
string EncodedString = System.Web.HttpUtility.HtmlEncode(TestString);
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SetUnhandledExceptionFilter and the C/C++ Runtime Library - C/C++ - 清泛网移动版 - 专注IT技能提升
...(JIT) debugger if such a debugger is installed on the system.
In order to test the code, we will simulate a null pointer invalid access like this:
int main()
{
::SetUnhandledExceptionFilter(OurCrashHandler);
std::cout << "Normal null pointer crash" << std::endl;
char *p = 0;
...
SetUnhandledExceptionFilter and the C/C++ Runtime Library - C/C++ - 清泛网移动版 - 专注IT技能提升
...(JIT) debugger if such a debugger is installed on the system.
In order to test the code, we will simulate a null pointer invalid access like this:
int main()
{
::SetUnhandledExceptionFilter(OurCrashHandler);
std::cout << "Normal null pointer crash" << std::endl;
char *p = 0;
...