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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the row won't actually be inserted if it results in a duplicate key. But the statement won't generate an error. It generates a warning instead. These cases include:
Inserting a duplicate key in columns with PRIMARY KEY or UNIQUE constrain...
How to make a cross-module variable?
...as if a global from any other module that includes __builtin__ -- which is all of them, by default.
a.py contains
print foo
b.py contains
import __builtin__
__builtin__.foo = 1
import a
The result is that "1" is printed.
Edit: The __builtin__ module is available as the local symbol __builtin...
jQuery or CSS selector to select all IDs that start with some string [duplicate]
How can I select all elements whose id starts with "player_"?
4 Answers
4
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What is a None value?
...n't write the sticker "F", there was already an F sticker on the None, and all you did was move it, from None to "fork". So when you type F = None, you're "reset[ting] it to its original, empty state", if we decided to treat None as meaning empty state.
I can see what he's getting at, but that's a...
What is the best way to compute trending topics or tags?
...
This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the avera...
ASP.NET MVC - TempData - Good or bad practice
...e it would be gone. Well I guess I'm also hesitant to use it as its not really well defined how reliable it is.
I wonder if the problem is that you're having the action redirect to another page before the confirm step. I wonder if instead after they first submit, you could do enough processing to...
How to check if the string is empty?
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s.strip() allocates a new string, which is pure waste. Use string.isspace()
– Clément
Jun 22 at 15:27
add a ...
How do you do Impersonation in .NET?
...asy
WindowsIdentity.Impersonate Method (check out the code samples)
Basically you will be leveraging these classes that are out of the box in the .NET framework:
WindowsImpersonationContext
WindowsIdentity
The code can often get lengthy though and that is why you see many examples like the on...
How to create a unique index on a NULL column?
...rver 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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What is the lifetime of a static variable in a C++ function?
... scope it is only initialized once and retains its value between function calls. What exactly is its lifetime? When do its constructor and destructor get called?
...