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How to get JSON objects value if its name contains dots?
I have a very simple JSON array (please focus on "points.bean.pointsBase" object):
5 Answers
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Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need ...
rails + MySQL on OSX: Library not loaded: libmysqlclient.18.dylib
....18.dylib /usr/lib/libmysqlclient.18.dylib
There are many blogs with install_name_tool, which won't work for me because I'm on OSX Lion:
sudo install_name_tool -change libmysqlclient.18.dylib /usr/local/mysql/lib/libmysqlclient.18.dylib /usr/local/bin/indexer
sudo install_name_tool -change libmys...
Using success/error/finally/catch with Promises in AngularJS
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Promises are an abstraction over statements that allow us to express ourselves synchronously with asynchronous code. They represent a execution of a one time task.
They also provide exception handling, just like normal code, you can return from a promise or you can throw.
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round up to 2 decimal places in java? [duplicate]
...s 395034 is nearest long that is then divided by 100. However I think generally people would expect the result as 395.04.
– Vishal Saxena
Oct 3 '18 at 15:46
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When saving, how can you check if a field has changed?
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Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharF...
The case against checked exceptions
...jlsberg and his work, this argument has always struck me as bogus. It basically boils down to:
"Checked exceptions are bad because programmers just abuse them by always catching them and dismissing them which leads to problems being hidden and ignored that would otherwise be presented to the us...
How can I iterate over an enum?
... Two = 9,
Three = 4,
Last
};
This illustrates that an enum is not really meant to iterate through. The typical way to deal with an enum is to use it in a switch statement.
switch ( foo )
{
case One:
// ..
break;
case Two: // intentional fall-through
case Three:
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What exactly are DLL files, and how do they work?
... files, ...) that an EXE, or other DLL uses.
Types of libraries:
On virtually all operating systems, there are 2 types of libraries. Static libraries and dynamic libraries. In windows the file extensions are as follows: Static libraries (.lib) and dynamic libraries (.dll). The main difference i...
How to get a list of all files that changed between two Git commits?
Due to bureaucracy, I need to get a list of all changed files in my repository for a report (I started with existing source code).
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