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ORA-00979 not a group by expression
...ults to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like this:
FOO BAR
0 A
0 B
and you run SELECT * FROM table GROUP BY foo. This means the database must return a single row as result with the first column 0 to fulfill t...
How can I add a string to the end of each line in Vim?
... @dirkgently How can I pass a string variable as an argument to this command (you know, instead of the *) ?
– Matheus Rotta
Sep 4 '17 at 22:24
add a comment
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Converting camel case to underscore case in ruby
...ls so you can't call underscore by default, but by providing the code used and citing rails as the source this answer is a good one for ruby, It says you can include rails, or just include this function that the rails team wrote and have tested.
– Michael Gorman
...
What does !! mean in ruby?
...ly not necessary to use though since the only false values to Ruby are nil and false, so it's usually best to let that convention stand.
Think of it as
!(!some_val)
One thing that is it used for legitimately is preventing a huge chunk of data from being returned. For example you probably don't ...
How do you get the length of a string?
...
You don't need jquery, just use yourstring.length. See reference here and also here.
Update:
To support unicode strings, length need to be computed as following:
[..."????"].length
or create an auxiliary function
function uniLen(s) {
return [...s].length
}
...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
... a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the.lock
[Terminal #2] lockfile: Sorry, giving up on "/tmp/the.lock"
[Terminal #1] $ rm -f /tmp/the....
How to detect if a function is called as constructor?
...
NOTE: This is now possible in ES2015 and later. See Daniel Weiner's answer.
I don't think what you want is possible [prior to ES2015]. There simply isn't enough information available within the function to make a reliable inference.
Looking at the ECMAScript 3...
How to add anything in through jquery/javascript?
...
You can select it and add to it as normal:
$('head').append('<link />');
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Python string prints as [u'String']
...duces Unicode. So you need to convert the list to a single unicode string, and then convert that to ASCII.
I don't know exaxtly how you got the one-element lists; the contents member would be a list of strings and tags, which is apparently not what you have. Assuming that you really always get a li...
std::string to float or double
...
The Standard Library (C++11) offers the desired functionality with std::stod :
std::string s = "0.6"
std::wstring ws = "0.7"
double d = std::stod(s);
double dw = std::stod(ws);
Generally for most other basic types, see <st...