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Why is it said that “HTTP is a stateless protocol”?
...ocket. That is solely a performance thing, intended to minimize the time/bandwidth that'd otherwise be spent reestablishing a connection for each request.
As far as HTTP is concerned, they are all still separate requests and must contain enough information on their own to fulfill the request. Tha...
INNER JOIN vs LEFT JOIN performance in SQL Server
I've created SQL command that uses INNER JOIN on 9 tables, anyway this command takes a very long time (more than five minutes). So my folk suggested me to change INNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got si...
How do I execute a string containing Python code in Python?
...ting code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, to see if these can better meet your needs.
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Why am I getting this error: No mapping specified for the following EntitySet/AssociationSet - Entit
... state that the SSDL does not exist. You can drag entities, associate them and so forth and yet, if you take a look at the SSDL on the EDMX file, you will see that none of the entities have an associated storage table in the SSDL.
That changes when you click the Generate Database From Model context...
Function pointers, Closures, and Lambda
I am just now learning about function pointers and, as I was reading the K&R chapter on the subject, the first thing that hit me was, "Hey, this is kinda like a closure." I knew this assumption is fundamentally wrong somehow and after a search online I didn't find really any analysis of this compari...
Finalize vs Dispose
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Others have already covered the difference between Dispose and Finalize (btw the Finalize method is still called a destructor in the language specification), so I'll just add a little about the scenarios where the Finalize method comes in handy.
Some types encapsulate disposable res...
DateTime vs DateTimeOffset
Currently, we have a standard way of dealing with .NET DateTime 's in a TimeZone aware way: Whenever we produce a DateTime we do it in UTC (e.g. using DateTime.UtcNow ), and whenever we display one, we convert back from UTC to the user's local time.
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Threading in a PyQt application: Use Qt threads or Python threads?
...humb might be to use QThreads if you're going to interact somehow with Qt, and use Python threads otherwise.
And some earlier comment on this subject from PyQt's author: "they are both wrappers around the same native thread implementations". And both implementations use GIL in the same way.
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Transactions in REST?
...er. In the same way that you can add multiple items to a shopping basket and then submit that basket to process the order, you can add Bob's account entry to the transaction wrapper and then Bill's account entry to the wrapper. When all the pieces are in place then you can POST/PUT the transacti...
Java Delegates?
...same effect by using reflection to get Method objects you can then invoke, and the other way is to create an interface with a single 'invoke' or 'execute' method, and then instantiate them to call the method your interested in (i.e. using an anonymous inner class).
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