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How do I use ROW_NUMBER()?
...ases, despite their name, don't have a formal ordering, so if you want to call a row "1" or "10" or "1337", you need to order them first using an ORDER BY clause, which is the one that goes in the OVER (ORDER BY X) clause.
– Wtrmute
Sep 13 '17 at 0:25
...
What is the error “Every derived table must have its own alias” in MySQL?
...hout their names (or aliases) so, you must give unique names (aliases) for all of your sub-queries to make dbms query engine make it's work properly."
– Bahadir Tasdemir
Apr 25 '16 at 7:33
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Get list of a class' instance methods
...
You actually want TestClass.instance_methods, unless you're interested in what TestClass itself can do.
class TestClass
def method1
end
def method2
end
def method3
end
end
TestClass.methods.grep(/method1/) # => []
...
Purpose of returning by const value? [duplicate]
...
In the hypothetical situation where you could perform a potentially expensive non-const operation on an object, returning by const-value prevents you from accidentally calling this operation on a temporary. Imagine that + returned a non-const value, and you could write:
(a + b).expensiv...
Import error: No module name urllib2
...ython 3 named urllib.request and urllib.error. The 2to3 tool will automatically adapt imports when converting your sources to Python 3.
So you should instead be saying
from urllib.request import urlopen
html = urlopen("http://www.google.com/").read()
print(html)
Your current, now-edited code sa...
How can I check if a scrollbar is visible?
...s been shrunk by the horizontal scroll bar height.
– Ally
Jul 3 '12 at 10:36
why you have defined same function two ti...
Convert string to variable name in JavaScript
...ontext. this is context, what it points to depends on how the function is called. In JS, 50% of the time this is window unless you enable strict mode and this becomes undefined and will throw an error. Scope is something completely different and it's not an object (except global scope which is mirro...
I keep getting “Uncaught SyntaxError: Unexpected token o”
...guess about the datatype. It does the JSON parsing even though you're not calling getJSON()-- then when you try to call JSON.parse() on an object, you're getting the error.
Further explanation can be found in Aditya Mittal's answer.
...
About Android image and asset sizes
...dpi
0.75 | 1 | 1.33 | 1.5 | 2 | 3 | 4
Although you don't really need to worry about tvdpi unless you're developing specifically for Google TV or the original Nexus 7 -- but even Google recommends simply using hdpi assets.
What this means is if you're doing a 48dip image and plan to ...
Func vs. Action vs. Predicate [duplicate]
...cher.BeginInvoke.
Predicate is just a special cased Func<T, bool> really, introduced before all of the Func and most of the Action delegates came along. I suspect that if we'd already had Func and Action in their various guises, Predicate wouldn't have been introduced... although it does impa...