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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 ...
A generic error occurred in GDI+, JPEG Image to MemoryStream
This seems to be a bit of an infamous error all over the web. So much so that I have been unable to find an answer to my problem as my scenario doesn't fit. An exception gets thrown when I save the image to the stream.
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Purge or recreate a Ruby on Rails database
...o this:
This will reset your database and reload your current schema with all:
rake db:reset db:migrate
This will destroy your db and then create it and then migrate your current schema:
rake db:drop db:create db:migrate
All data will be lost in both scenarios.
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#pragma once vs include guards? [duplicate]
... time but #pragma once is very well supported across compilers but not actually part of the standard. The preprocessor may be a little faster with it as it is more simple to understand your exact intent.
#pragma once is less prone to making mistakes and it is less code to type.
To speed up compil...
How many and which are the uses of “const” in C++?
...structor of it doesn't need to be virtual - the right destructor is still called:
ScopeGuard const& guard = MakeGuard(&cleanUpFunction);
Explanation, using code:
struct ScopeGuard {
~ScopeGuard() { } // not virtual
};
template<typename T> struct Derived : ScopeGuard {
T ...
How to round to 2 decimals with Python?
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That is called bankers rounding. It rounds towards the even number. It's in the IEEE 754 standard for floating point numbers. en.wikipedia.org/wiki/Rounding#Round_half_to_even
– rolisz
Dec 9 '13...
execute function after complete page load
... why jQuery will most probably implement some heavy workarounds to support all the browsers. And this will make it very difficult to "exactly" simulate the behavior using plain Javascript (but not impossible of course).
as Jeffrey Sweeney and J Torres suggested, i think its better to have a setTime...
what’s the difference between Expires and Cache-Control headers?
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It's worth commenting that cache-control is what all browsers will use, but it's useful to specify both headers just in case there are old proxies in the way.
– Nacho Coloma
Sep 17 '12 at 14:33
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foldl versus foldr behavior with infinite lists
...ed. If f always uses its first argument, this means Haskell has to recurse all the way down to the innermost term, then work backwards computing each application of f.
This is obviously a far cry from the efficient tail-recursion most functional programmers know and love!
In fact, even though fold...
Found conflicts between different versions of the same dependent assembly that could not be resolved
...s say this, they don't make it explicit, so I will....
On VS2013.2, to actually trigger the emission of the cited information, you need to not read the message, which says:
C:\Program Files (x86)\MSBuild\12.0\bin\Microsoft.Common.CurrentVersion.targets(1697,5): warning MSB3277: Found conflicts betw...