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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 does SIGPIPE exist?
...ing the read, but during the write. You don't need to write a C program to test it, just run cat | head, and pkill head in a separate terminal. You'll see that cat happily lives on waiting in its read()—only when you type something in and press enter does cat die with a broken pipe, exactly becaus...
How does Go compile so quickly?
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A good test for the translation efficiency of a compiler is self-compilation: how long does it take a given compiler to compile itself? For C++ it takes a very long time (hours?). By comparison, a Pascal/Modula-2/Oberon compiler wou...
navigator.geolocation.getCurrentPosition sometimes works sometimes doesn't
...ded the solution because I needed it for a site I was working on. Have you tested?
– going
Nov 7 '12 at 21:55
sorry,it...
Git vs Team Foundation Server [closed]
...ance, if I'm working on a big feature, it might take me a week to code and test it completely. I don't want to check-in unstable code mid-week and break the build, but what happens if I'm nearing the end of the week and I accidentally bork my entire working copy? If I haven't been committing all a...
what exactly is device pixel ratio?
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sadly, you have to google it or test on a real device :(
– netalex
Feb 19 '16 at 9:53
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Is Java Regex Thread Safe?
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@DavidTonhofer I think our latest JDK may have the correct bug-free code, but since Java's intermediate .class files can be interpreted on any platform by any compatible VM, you can't be sure those fixes exist in that runtime. Of course most of the time ...
What is the purpose of python's inner classes?
... to see whats going on.
Nested classes can create coupling that would make testing more difficult.
In Python you can put more than one class in a file/module, unlike Java, so the class still remains close to top level class and could even have the class name prefixed with an "_" to help signify that...
Greedy vs. Reluctant vs. Possessive Quantifiers
..."foo"
The initial nothing is consumed by .?*, which will consume the shortest possible amount of anything that allows the rest of the regex to match.
doesn't appear at the beginning of the
string, it's forced to swallow (who swallows?) the
Again the .?* consumes the first character, after ...
Why are local variables not initialized in Java?
...ompiler understands that if check (but i m just doing this off memory, not tested).
– Chii
Jan 6 '09 at 9:52
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