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delete_all vs destroy_all?
...any tables. I want to delete this user and every record that has his ID in all tables.
4 Answers
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Java EE 6 @javax.annotation.ManagedBean vs. @javax.inject.Named vs. @javax.faces.ManagedBean
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First of all let me do some clarifications:
Managed bean definition : generally a managed bean is an object that its life cycle (construction, destruction, etc) is managed by a container.
In Java ee we have many containers that mana...
.NET - Dictionary locking vs. ConcurrentDictionary
... a can from a pyramid-can while a clerk is currently building the pyramid, all hell would break loose. Or, what if two customers reaches for the same item at the same time, who wins? Will there be a fight? This is a non-threadsafe-collection. There's plenty of ways to avoid problems, but they all re...
Why is require_once so bad to use?
...system keeps a log of what's already been included/required. Every *_once call means checking that log. So there's definitely some extra work being done there but enough to detriment the speed of the whole app?
... I really doubt it... Not unless you're on really old hardware or doing it a lot.
I...
Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
Visual Studio Editor does not underline errors anymore
...tor has stopped to underline Errors (this nifty wavy red lines). I can't really tell when, but it can be related to the installation of .Net Framework 3.5 SP 1 or the MVC Beta (which I guess is unlikely). Furthermore have I installed and uninstalled both CodeRush and Resharper for evaluation purpose...
Stop Visual Studio from launching a new browser window when starting debug?
...ess the running application, but it won't open the browser window automatically, it'll just start in the background and wait for any requests.
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The Following Module was built either with optimizations enabled or without debug information
...ode on the non-web project in question and it's in Active(Debug). Deleted all items in my .NET 2.0 temp folder in Windows. Not sure what else to do here.
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What are naming conventions for MongoDB?
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Keep'em short: Optimizing Storage of Small Objects, SERVER-863. Silly but true.
I guess pretty much the same rules that apply to relation databases should apply here. And after so many decades there is still no agreement whether RDBMS tables should be named singul...
Count(*) vs Count(1) - SQL Server
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There is no difference.
Reason:
Books on-line says "COUNT ( { [ [ ALL | DISTINCT ] expression ] | * } )"
"1" is a non-null expression: so it's the same as COUNT(*).
The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SE...