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PostgreSQL return result set as JSON array?
...up
The json_agg function produces this result out of the box. It automatically figures out how to convert its input into JSON and aggregates it into an array.
SELECT json_agg(t) FROM t
There is no jsonb (introduced in 9.4) version of json_agg. You can either aggregate the rows into an array and ...
Enumerable.Empty() equivalent for IQueryable
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@Nauman - you actually create an [empty] T array - no new object of T is actually created.
– zastrowm
Feb 20 '14 at 15:56
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Casting a variable using a Type variable
...th a value of 1000, the compiler
// doesn't know the exact type so it will allow you to call any
// property or method on it, but will crash if it doesn't exist
dynamic value3 = Convert.ChangeType(value1, intType);
I've written the answer with generics, because I think it is a very likely sign of ...
Best way to specify whitespace in a String.Split operation
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If you just call:
string[] ssize = myStr.Split(null); //Or myStr.Split()
or:
string[] ssize = myStr.Split(new char[0]);
then white-space is assumed to be the splitting character. From the string.Split(char[]) method's documentation page...
Save ArrayList to SharedPreferences
...Set the values
Set<String> set = new HashSet<String>();
set.addAll(listOfExistingScores);
scoreEditor.putStringSet("key", set);
scoreEditor.commit();
You can also serialize your ArrayList and then save/read it to/from SharedPreferences. Below is the solution:
EDIT:
Ok, below is the sol...
Why does Python code use len() function instead of a length method?
...on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in iter() function (or have the method called behind the scenes for you) on objects which are iterable.
See Emulating container types for m...
What exactly is an “open generic type” in .NET? [duplicate]
...er a type argument or a generic type defined with unknown type arguments:
All types can be classified as either open types or closed types. An open type is a type that involves type parameters. More specifically:
A type parameter defines an open type.
An array type is an open type if and only if i...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
Right way to initialize an OrderedDict using its constructor such that it retains order of initial d
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Why does Vim save files with a ~ extension?
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Actually - do I have to have both nobackup and nowritebackup? Is there a way to write a copy of the file as a backup, but not do this write/delete/rename stuff?
– Merlyn Morgan-Graham
Mar 2...