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selecting unique values from a column
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Narendrasingh Sisodia
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answered Dec 20 '11 at 7:10
Léon RodenburgLéon ...
Array include any value from another array?
... & foods).empty?
As Marc-André Lafortune said in comments, & works in linear time while any? + include? will be quadratic. For larger sets of data, linear time will be faster. For small data sets, any? + include? may be faster as shown by Lee Jarvis' answer -- probably because & alloc...
Gson: Directly convert String to JsonObject (no POJO)
...ttempting JSON tree manipulation in GSON, but I have a case where I do not know or have a POJO to convert a string into, prior to converting to JsonObject . Is there a way to go directly from a String to JsonObject ?
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Javascript shorthand ternary operator
I know that in php 5.3 instead of using this redundant ternary operator syntax:
7 Answers
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Storyboard warning: prototype table cells must have reuse identifiers
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alerootaleroot
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How do you list the active minor modes in emacs?
...de-list. Finding out whether they're active or not is usually done by checking the variable of the same name. So you can do something like this:
(defun which-active-modes ()
"Give a message of which minor modes are enabled in the current buffer."
(interactive)
(let ((active-modes))
(map...
Macro vs Function in C
...rone because they rely on textual substitution and do not perform type-checking. For example, this macro:
#define square(a) a * a
works fine when used with an integer:
square(5) --> 5 * 5 --> 25
but does very strange things when used with expressions:
square(1 + 2) --> 1 + 2 * 1 + 2 ...
Using current time in UTC as default value in PostgreSQL
I have a column of the TIMESTAMP WITHOUT TIME ZONE type and would like to have that default to the current time in UTC. Getting the current time in UTC is easy:
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android: stretch image in imageview to fit screen
... I suppose this should set my images to fit the screen. But it only fits like 80% (margin top and bottom in landscape mode).
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What is the difference between IEqualityComparer and IEquatable?
...d IEquatable<T> should be used.
The MSDN documentation for both looks very similar.
5 Answers
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