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Postgresql aggregate array
...
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 to repeat the columns on SE...
is there an virtual environment for node.js?
...kages is your main issue, then maybe consider using the very cool 'bundle' command with npm. This is closer to freezing gems or using bundler in rails, rather than rvm.
It's super easy. Just create a package.json file:
{ "name": "yourapp", "version": "0.0.1", "dependencies": {"jade": "0.4.1"}}
a...
EOFError: end of file reached issue with Net::HTTP
...uest_uri)
req.set_form_data({'name'=>'Sur Max', 'email'=>'some@email.com'})
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = (url.scheme == "https")
response = http.request(req)
See more in my blog: EOFError: end of file reached issue when post a form with Net::HTTP.
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OnItemCLickListener not working in listview
...your_xml_file.xml)
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:baselineAligned="false"
android:descendantFocusability="blocksDescendants"
android:gravity="center_vert...
CoInitialize浅析一 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
CoInitialize浅析一大家都知道程序中若要使用COM组件则必须要先调用CoInitialize，该函数主要是用来初始化COM运行环境。但这个函数的作用域是以线程为单位还是 大家都知道程序中若要使用COM组件则必须要先调用CoInitialize，该函数...
How to share my Docker-Image without using the Docker-Hub?
...
Docker images are stored as filesystem layers. Every command in the Dockerfile creates a layer. You can also create layers by using docker commit from the command line after making some changes (via docker run probably).
These layers are stored by default under /var/lib/docker...
PHP function to generate v4 UUID
...at generates a valid v4 UUID in PHP. This is the closest I've been able to come. My knowledge in hex, decimal, binary, PHP's bitwise operators and the like is nearly non existant. This function generates a valid v4 UUID up until one area. A v4 UUID should be in the form of:
...
What's the difference between libev and libevent?
...ely in multithreaded environments, watcher structures are big because they combine I/O, time and signal handlers in one, the extra components such as the http and dns servers suffered from bad implementation quality and resultant security issues, and timers were inexact and didn't cope well with tim...
Android Studio IDE: Break on Exception
...lass namespace patterns by clicking on the (Add Pattern) button. Enter:
com.myapp.* (replace this with the namespace prefix of your app)
java.* (note: as per OP's question, leave this out to NOT break on Java libraries)
android.* (as above, leave out to just debug own app code)
Add any additional...