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How to Join to first row
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SELECT Orders.OrderNumber, LineItems.Quantity, LineItems.Description
FROM Orders
JOIN LineItems
ON LineItems.LineItemGUID =
(
SELECT TOP 1 LineItemGUID
FROM LineItems
WHERE OrderID = Orders.OrderI...
Most efficient way to concatenate strings in JavaScript?
In JavaScript, I have a loop that has many iterations, and in each iteration, I am creating a huge string with many += operators. Is there a more efficient way to create a string? I was thinking about creating a dynamic array where I keep adding strings to it and then do a join. Can anyone explain...
Change UICollectionViewCell size on different device orientations
I am using an UICollectionView with UICollectionViewFlowLayout .
6 Answers
6
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How do I make a transparent canvas in html5?
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Canvases are transparent by default.
Try setting a page background image, and then put a canvas over it. If nothing is drawn on the canvas, you can fully see the page background.
Think of a canvas as like painting on a glass plate.
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Please explain about insertable=false and updatable=false in reference to the JPA @Column annotation
If a field is annotated insertable=false, updatable=false , doesn't it mean that you cannot insert value nor change the existing value? Why would you want to do that?
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Simple example of threading in C++
Can someone post a simple example of starting two (Object Oriented) threads in C++.
7 Answers
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What is the difference between DAO and Repository patterns?
...nce between Data Access Objects (DAO) and Repository patterns? I am developing an application using Enterprise Java Beans (EJB3), Hibernate ORM as infrastructure, and Domain-Driven Design (DDD) and Test-Driven Development (TDD) as design techniques.
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In ASP.NET, when should I use Session.Clear() rather than Session.Abandon()?
... ends the current session, and causes a new session to be created thus causing the End and Start events to fire.
4 Answers
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Unnamed/anonymous namespaces vs. static functions
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The C++ Standard reads in section 7.3.1.1 Unnamed namespaces, paragraph 2:
The use of the static keyword is
deprecated when declaring objects in a
namespace scope, the unnamed-namespace
provides a superior alternative.
Static only a...
Laravel Check If Related Model Exists
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In php 7.2+ you can't use count on the relation object, so there's no one-fits-all method for all relations. Use query method instead as @tremby provided below:
$model->relation()->exists()
generic solution working...