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Create unique constraint with null columns
...rom favo_3col_uni_idx and your requirements are still enforced.
The index, now comprising the whole table, overlaps with the other one and gets bigger. Depending on typical queries and the percentage of NULL values, this may or may not be useful. In extreme situations it might even help to maintain ...
Functions that return a function
... to the function, which can be assigned as you've done with var s = a(). s now contains a reference to the function b(), and calling s() is functionally equivalent to calling b().
// Return a reference to the function b().
// In your example, the reference is assigned to var s
return b;
Calling t...
How to get StackPanel's children to fill maximum space downward?
... the last hour trying to figure out how to get StackPanel to do this. From now on, I'll look here first for my WPF (and other) info.
– paxdiablo
Jun 22 '10 at 15:05
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nServiceBus vs Mass Transit vs Rhino Service Bus vs other?
...
I'm still getting used to the fact that people are now discovering NServiceBus who do not know that I created it
– Udi Dahan
Nov 10 '10 at 10:38
5
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Best practice for Python assert
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assert should only be used to catch problems with no known recovery; almost always code bugs (not bad inputs). when an assert is triggered, it should mean that the program is in a state that may be dangerous to continue in, as it may start talking to the network or writing to d...
Should I use a data.frame or a matrix?
...ize. To adapt the new version of the function to ggplot(), I converted the now returned matrix to a data.frame to use in ggplot().
After I rerun the code I could not believe the result. The code run in a fraction of a second! Instead of about 12 seconds. And again, the function during the 10,000 i...
When to use next() and return next() in Node.js
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@AdamD I would like to know that as well.
– theprogrammer
Sep 1 at 23:01
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Why should C++ programmers minimize use of 'new'?
... it's less limited.
Two key reasons to use dynamic allocation:
You don't know how much memory you need at compile time. For instance, when reading a text file into a string, you usually don't know what size the file has, so you can't decide how much memory to allocate until you run the program.
Y...
Stopping python using ctrl+c
...get=work)
t.daemon = True
t.start()
#install handler
install_handler()
# now block
t.join()
#Ctrl+C works now!
Solution 3: Polling method
I don't prefer or recommend this method because it unnecessarily consumes processor and power negatively impacting the performance.
import threading
import...
Can I run multiple versions of Google Chrome on the same machine? (Mac or Windows)
...Also extract this file, and descend the created Chrome-bin
directory. Now, you see chrome.exe and a dir like 18.0.1025.45.
Move chrome.exe to 18.0.1025.45, then move this directory to
C:\Chrome. The remaining files in Chrome-bin can safely be
deleted.
Create a shortcut for each version:...