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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 SELECT to GROUP BY,...
multiprocessing: sharing a large read-only object between processes?
...rom many sources.
Reading from many named pipes is often done using the select module to see which pipes have pending input.
Solution 3
Shared lookup is the definition of a database.
Solution 3A – load a database. Let the workers process the data in the database.
Solution 3B – create...
Adding devices to team provisioning profile
...e.com
Add the UDID in devices
Go back to XCode, open up the Organizer and select "Provisioning Profiles", ensure that "Automatic Device Provisioning" is checked on the top right pane, then click on the "Refresh" button, and magically all your devices set in the provisioning portal will be automati...
Printing the correct number of decimal points with cout
...d/
#include <iostream>
#include <iomanip>
int main(int argc, char** argv)
{
float testme[] = { 0.12345, 1.2345, 12.345, 123.45, 1234.5, 12345 };
std::cout << std::setprecision(2) << std::fixed;
for(int i = 0; i < 6; ++i)
{
std::cout << tes...
SQL- Ignore case while searching for a string
...
Use something like this -
SELECT DISTINCT COL_NAME FROM myTable WHERE UPPER(COL_NAME) LIKE UPPER('%PriceOrder%')
or
SELECT DISTINCT COL_NAME FROM myTable WHERE LOWER(COL_NAME) LIKE LOWER('%PriceOrder%')
...
ReactJS render string with non-breaking spaces
I have some props that has a string that could contain characters such as &.
It also contains spaces. I want to replace all spaces with &nbsp; .
...
Resharper- Find all unused classes
... find unused references of a single file by right clicking on the file and selecting the "Find Usages" option. Is there any way I can see or get the list of all the unused classes or files in my project ?
...
Git 工具 - 子模块(submodule)：一个仓库包含另一个仓库 - 开源 & Github -...
.../src/main.c
@@ -245,6 +245,8 @@ static int handle_alias(int *argcp, const char ***argv)
commit_pager_choice();
+ url = url_decode(url_orig);
+
/* build alias_argv */
alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
alias_argv[0] = alias_string + 1;
Ente...
How to get an object's properties in JavaScript / jQuery?
...ct. Even most of those primitives are actually also objects with a limited selection of methods. They are cast into objects under the hood, when required. To know the base class name, you may invoke the Object.prototype.toString method on an object, like this:
alert(Object.prototype.toString.call([...
Permission denied (publickey) when SSH Access to Amazon EC2 instance [closed]
...these steps:
Access to AWS Management Console
Open Elastic Beanstalk Tab
Select your application from All Applications Tab
From left side menù select Configuration
Click on the Instances Gear
In Server Form check the EC2 Key Pair input and select your new Key Pair. You may have to refresh the lis...