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Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) fro...
Gradient of n colors ranging from color 1 and color 2
...adients nice ( click here for an example ). I have a need to work in base and I think scales can be used there to create color gradients as well but I'm severely off the mark on how. The basic goal is generate a palette of n colors that ranges from x color to y color. The solution needs to work...
Calculate the number of business days between two dates?
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I've had such a task before and I've got the solution.
I would avoid enumerating all days in between when it's avoidable, which is the case here. I don't even mention creating a bunch of DateTime instances, as I saw in one of the answers above. This is ...
Converting bytes to megabytes
... it is not correct actually because mega means 1 000 000. There is a new standard name for 220 bytes, it is mebibyte (http://en.wikipedia.org/wiki/Mebibyte) and it gathers popularity.
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Elegant ways to support equivalence (“equality”) in Python classes
...om classes it is often important to allow equivalence by means of the == and != operators. In Python, this is made possible by implementing the __eq__ and __ne__ special methods, respectively. The easiest way I've found to do this is the following method:
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Formatting floats without trailing zeros
...t formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
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How do I decode a string with escaped unicode?
... to http://example.com with JavaScript? I tried unescape , decodeURI , and decodeURIComponent so I guess the only thing left is string replace.
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Valid values for android:fontFamily and what they map to?
In the answer to this question the user lists values for android:fontFamily and 12 variants (see below). Where do these values come from? The documentation for android:fontFamily does not list this information in any place (I checked here , and here ). The strings are listed in the Android ...
How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fact 0 = 1
fact n =...
How do I use prepared statements in SQlite in Android?
How do I use prepared statements in SQlite in Android?
5 Answers
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