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Oracle “Partition By” Keyword
Can someone please explain what the partition by keyword does and give a simple example of it in action, as well as why one would want to use it? I have a SQL query written by someone else and I'm trying to figure out what it does.
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PHP Sort Array By SubArray Value
...['optionNumber'] - $b['optionNumber'];
});
Note that both code above assume $a['optionNumber'] is an integer. Use @St. John Johnson's solution if they are strings.
In PHP ≥7.0, use the spaceship operator <=> instead of subtraction to prevent overflow/truncation problems.
usort($array, ...
Google Play on Android 4.0 emulator
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Download Google apps (GoogleLoginService.apk , GoogleServicesFramework.apk , Phonesky.apk) from here.
Start your emulator:
emulator -avd VM_NAME_HERE -partition-size 500 -no-audio -no-boot-anim
Then use the following commands:
# Remount in rw mode.
# NOTE: more recent system.img files a...
What is the difference D3 datum vs. data?
Can someone please explain the difference between datum() and data() in D3.js? I see both being used and I am not sure why you should choose one over the other?
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how do i block or restrict special characters from input fields with jquery?
... It doesn't works in latest firefox brower, but working fine in chrome
– Phoenix
Dec 31 '18 at 11:57
This solut...
How to count TRUE values in a logical vector
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There are some problems when logical vector contains NA values.
See for example:
z <- c(TRUE, FALSE, NA)
sum(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing retur...
How to create a directory and give permission in single command
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According to mkdir's man page...
mkdir -m 777 dirname
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How to get a random number in Ruby
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Finally, if you just need a random float, just call rand with no arguments.
As Marc-André Lafortune mentions in his answer below (go upvote it), Ruby 1.9.2 has its own Random class (that Marc-André himself helped to debug, hence the 1.9.2 target for that feature).
For instance, in this ...
Is it possible to ping a server from Javascript?
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I have found someone that accomplishes this with a very clever usage of the native Image object.
From their source, this is the main function (it has dependences on other parts of the source but you get the idea).
function Pinger_ping(ip...
store and retrieve a class object in shared preference
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Thanks.I want to store some data members of the class.And i don't want to store each values of data members using shared preference.I want to store it as an object.If not shared preference what are my other options?
– androidGuy...