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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 ...
Why is a div with “display: table-cell;” not affected by margin?
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Cause
From the MDN documentation:
[The margin property] applies to all elements except elements with
table display types other than table-caption, table and inline-table
In other words, the margin property is not applicable to display:table-cell elements.
Solution
Consider using the bo...
Usages of Null / Nothing / Unit in Scala
...wered Apr 23 '13 at 16:40
pagoda_5bpagoda_5b
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HTTP Basic Authentication - what's the expected web browser experience?
When a server allows access via Basic HTTP Authentication, what is the experience expected to be in a web browser ?
6 Answ...
Determine Whether Two Date Ranges Overlap
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Proof:
Let ConditionA Mean that DateRange A Completely After DateRange B
_ |---- DateRange A ------|
|---Date Range B -----| _
(True if StartA > EndB)
Let ConditionB Mean that DateRange A is Completely Before DateRange B
|---- DateRange A ...
Loading cross-domain endpoint with AJAX
... API URL. (Supports https: see github repository)
If you want to automatically enable cross-domain requests when needed, use the following snippet:
$.ajaxPrefilter( function (options) {
if (options.crossDomain && jQuery.support.cors) {
var http = (window.location.protocol === 'http:'...
Real life example, when to use OUTER / CROSS APPLY in SQL
... ORDER BY pr.name) pa
ORDER BY pr.name,
pa.name
2) Calling a Table Valued Function for each row in the outer query
SELECT *
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle)
3) Reusing a column alias
SELECT number,
doubled_number...
Request Monitoring in Chrome
In Firefox, I use Firebug which allows me to view every http request my ajax calls are making. I've switched over my development to Chrome and am liking it so far. My only complaint, however, is that the developer tools don't seem to allow you to view each ajax request. I've had it happen once wh...
Different types of thread-safe Sets in Java
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1) The CopyOnWriteArraySet is a quite simple implementation - it basically has a list of elements in an array, and when changing the list, it copies the array. Iterations and other accesses which are running at this time continue with the old array, avoiding necessity of synchronization between...
How to view the Folder and Files in GAC?
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Install:
gacutil -i "path_to_the_assembly"
View:
Open in Windows Explorer folder
.NET 1.0 - NET 3.5: c:\windows\assembly (%systemroot%\assembly)
.NET 4.x: %windir%\Microsoft.NET\assembly
OR gacutil –l
When you are ...