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Counting null and non-null values in a single query
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If I understood correctly you want to count all NULL and all NOT NULL in a column...
If that is correct:
SELECT count(*) FROM us WHERE a IS NULL
UNION ALL
SELECT count(*) FROM us WHERE a IS NOT NULL
Edited to have the full query, after reading the comments :]
S...
How do I reverse a C++ vector?
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All containers offer a reversed view of their content with rbegin() and rend(). These two functions return so-calles reverse iterators, which can be used like normal ones, but it will look like the container is actually rever...
Unable to execute dex: method ID not in [0, 0xffff]: 65536
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Update 3 (11/3/2014)
Google finally released official description.
Update 2 (10/31/2014)
Gradle plugin v0.14.0 for Android adds support for multi-dex. To enable, you just have to declare it in build.gradle:
android {
defaultConfig {
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Why is spawning threads in Java EE container discouraged?
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It is discouraged because all resources within the environment are meant to be managed, and potentially monitored, by the server. Also, much of the context in which a thread is being used is typically attached to the thread of execution itself. If y...
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:
fac...
Is it possible to refresh a single UITableViewCell in a UITableView?
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The OP isn't animating anything, so there's no need to call the begin/endupdates
– kubi
Jul 15 '13 at 17:38
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How to select unique records by SQL
... answered Oct 29 '09 at 5:09
mjalldaymjallday
8,52877 gold badges4747 silver badges6868 bronze badges
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How do you search for files containing DOS line endings (CRLF) with grep on Linux?
...acters. By default it does this it if it decides it's a text file.
-r read all files under each directory recursively.
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How do I make a LinearLayout scrollable?
...it from the adapter functionality of the ListView, then you can simply add all the elements of your list in a LinearLayout wrapper to make it feel all streamlined in the scrollable box along with other elements.
– Atharva
Sep 19 '14 at 10:37
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Append a NumPy array to a NumPy array
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Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves c...