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PostgreSQL: Difference between text and varchar (character varying)
...able length array).
Check this article from Depesz: http://www.depesz.com/index.php/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/
A couple of highlights:
To sum it all up:
char(n) – takes too much space when dealing with values shorter than n (pads them to n), and can lead to subt...
Accessing elements of Python dictionary by index
...alues() on a dict to get a list of the inner dicts and thus access them by index.
>>> mydict = {
... 'Apple': {'American':'16', 'Mexican':10, 'Chinese':5},
... 'Grapes':{'Arabian':'25','Indian':'20'} }
>>>mylist = list(mydict.values())
>>>mylist[0]
{'American':'16', '...
Adding div element to body or document in JavaScript
... += '<div style="position:absolute;width:100%;height:100%;opacity:0.3;z-index:100;background:#000;"></div>';
instead of
document.body.innerHTML = '<div style="position:absolute;width:100%;height:100%;opacity:0.3;z-index:100;background:#000;"></div>';
Edit:-
Ideally you ...
Python pandas: fill a dataframe row by row
...of the elements)
In [7]: df = pandas.DataFrame(columns=['a','b','c','d'], index=['x','y','z'])
In [8]: df.loc['y'] = pandas.Series({'a':1, 'b':5, 'c':2, 'd':3})
In [9]: df
Out[9]:
a b c d
x NaN NaN NaN NaN
y 1 5 2 3
z NaN NaN NaN NaN
...
Pandas groupby: How to get a union of strings
... @VineeshTP: Column A was used as the grouping column, so it's in the index, as you can see in the example. You could get it back out as a column by using .reset_index().
– BrenBarn
Oct 9 '19 at 3:57
...
Get specific ArrayList item
...Also, be careful with the arrays indices: in Java, the first element is at index 0. So if you are trying to get the third element, your solution would be mainList.get(2);
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Angular JS break ForEach
...Script", "Java", "CoffeeScript", "TypeScript"];
ary.some(function (value, index, _ary) {
console.log(index + ": " + value);
return value === "JavaScript";
});
Example for every:
var ary = ["JavaScript", "Java", "CoffeeScript", "TypeScript"];
ary.every(function(value, index, _ary) {
...
How can I git stash a specific file?
...
@JamesJohnston git stash --keep-index will allow you to stash all the unstaged changes (the opposite of what you're looking for). stackoverflow.com/a/8333163/378253
– Nicolas Wormser
Oct 16 '13 at 11:23
...
What is the best collation to use for MySQL with PHP? [closed]
... ? are you sure about this ? publib.boulder.ibm.com/infocenter/db2luw/v9r5/index.jsp?topic=/… The collation you choose can significantly impact the performance of queries in the database.
– Adam Ramadhan
Aug 7 '10 at 7:54
...
How to move files from one git repo to another (not a clone), preserving history
...lected subdirectory. If you want to select just one file, have a look at --index-filter in the filter-branch manpage.
– Cascabel
Apr 3 '12 at 16:48
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