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Difference between Visibility.Collapsed and Visibility.Hidden
...have focus, you can't navigate to the control using the TAB key, etcetera, all of which still can if it would have a height and width of zero. But again, in terms of layout, you could say that.
– Razzie
May 20 '09 at 8:45
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What is the most frequent concurrency issue you've encountered in Java? [closed]
...are not synchronized this is not guaranteed to work. This mistake is especially devilish as in 99.999% it won't matter in practice as the reader thread will eventually see the change - but we don't know how soon he saw it.
s...
Should I call Close() or Dispose() for stream objects?
... StreamWriter etc implements IDisposable interface. That means, we can call Dispose() method on objects of these classes. They've also defined a public method called Close() . Now that confuses me, as to what should I call once I'm done with objects? What if I call both?
...
How to parse a string to an int in C++?
...g. ss << std::hex) before trying the conversion. But this means the caller must know a priori what base the number is -- and how can the caller possibly know that? The caller doesn't know what the number is yet. They don't even know that it is a number! How can they be expected to know what ba...
How to set variables in HIVE scripts
...em variables as well, so you can reference ${env:USER} for example.
To see all the available variables, from the command line, run
% hive -e 'set;'
or from the hive prompt, run
hive> set;
Update:
I've started to use hivevar variables as well, putting them into hql snippets I can include from hi...
Counting null and non-null values in a single query
...
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 to increase editor font size?
Font size in Android Studio editor seems to be too small.
18 Answers
18
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Oracle: If Table Exists
...her reason (that might be important) the exception is still raised to the caller:
BEGIN
EXECUTE IMMEDIATE 'DROP TABLE ' || table_name;
EXCEPTION
WHEN OTHERS THEN
IF SQLCODE != -942 THEN
RAISE;
END IF;
END;
ADDENDUM
For reference, here are the equivalent blocks for other...
how does multiplication differ for NumPy Matrix vs Array classes?
... and b) there's additional overhead compared to a "normal" numpy array. If all you're doing is linear algebra, then by all means, feel free to use the matrix class... Personally I find it more trouble than it's worth, though.
For arrays (prior to Python 3.5), use dot instead of matrixmultiply.
E.g...
How to define a function in ghci across multiple lines?
...
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...