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Is there any boolean type in Oracle databases?
...read on asktom. From recommending CHAR(1) 'Y'/'N' they switch to NUMBER(1) 0/1 when someone points out that 'Y'/'N' depends on the English language, while e.g. German programmers might use 'J'/'N' instead.
The worst thing is that they defend this stupid decision just like they defend the ''=NULL st...
Controlling maven final name of jar artifact
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303
You set the finalName property in the plugin configuration section:
<plugin>
<gro...
Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Python using enumerate inside list comprehension
...list)]
Either way, the result that gets returned is as expected:
> [(0, 'a'), (1, 'b'), (2, 'c'), (3, 'd')]
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What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it?
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300
Your first port of call should be the documentation which explains it reasonably clearly:
T...
How do I read / convert an InputStream into a String in Java?
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edited May 21 '18 at 13:09
Marko Zajc
14811 silver badge1313 bronze badges
answered Nov 21 '08 at 16:5...
How do I use arrays in C++?
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305
Arrays on the type level
An array type is denoted as T[n] where T is the element type and n is...
Check if an array is empty or exists
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if (typeof image_array !== 'undefined' && image_array.length > 0) {
// the array is defined and has at least one element
}
Your problem may be happening due to a mix of implicit global variables and variable hoisting. Make sure you use var whenever declaring a variable:
<?php e...
Regex to validate password strength
...itive look ahead assertions:
^(?=.*[A-Z].*[A-Z])(?=.*[!@#$&*])(?=.*[0-9].*[0-9])(?=.*[a-z].*[a-z].*[a-z]).{8}$
Rubular link
Explanation:
^ Start anchor
(?=.*[A-Z].*[A-Z]) Ensure string has two uppercase letters.
(?=.*[!@#$&*]) Ensure string ha...
How to wait in bash for several subprocesses to finish and return exit code !=0 when any subprocess
...ral subprocesses spawned from that script to finish and return exit code !=0 when any of the subprocesses ends with code !=0 ?
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