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SQL set values of one column equal to values of another column in the same table
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Sounds like you're working in just one table so something like this:
update your_table
set B = A
where B is null
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Should I use single or double colon notation for pseudo-elements?
... hand this is more verbose than necessary; for now, you can stick with the one-colon notation.
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How does PHP 'foreach' actually work?
...rm some kind of modification a real copy (called a "duplication") will be done. See You're being lied to for a more extensive introduction on this topic.
PHP 5
Internal array pointer and HashPointer
Arrays in PHP 5 have one dedicated "internal array pointer" (IAP), which properly supports modific...
How to cast List to List
...pointed. -- Meanwhile, .NET has two separate extension methods for this -- one called .Cast<T>() and one called .OfType<T>(). The former performs a cast on each element (throwing the desired exceptions) while the latter filters out elements that can't be cast (so you would pick one depe...
Is AsyncTask really conceptually flawed or am I just missing something?
...lieve that a class that flawed in design made it into the framework and no-one is talking about it, so I guess I just must be missing something.
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How do I run Redis on Windows?
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Wasn't one click for me. I've run the executable and still not sure how to get it to run
– Trevor de Koekkoek
May 12 '13 at 16:43
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Why is January month 0 in Java Calendar?
...ing from 0... except that days start with 1, of course. I doubt whether anyone outside the original implementation team could really state reasons - but again, I'd urge readers not to worry so much about why bad decisions were taken, as to look at the whole gamut of nastiness in java.util.Calendar a...
Eventual consistency in plain English
...e) came away thinking it is going to be sunny, even though she asked after one or more of the servers (you and me) had a more up-to-date value.
As opposed to Strict Consistency / ACID compliance:
Your bank balance is $50.
You deposit $100.
Your bank balance, queried from any ATM anywhere, is $150...
Difference between Repository and Service Layer?
...epository returns all users, ListUsers() of IUserService could return only ones, user has access to.
In ASP.NET MVC + EF + SQL SERVER, I have this flow of communication:
Views <- Controllers -> Service layer -> Repository layer -> EF -> SQL Server
Service layer -> Reposit...
Best way to use Google's hosted jQuery, but fall back to my hosted library on Google fail
...d be in the <body> to avoid errors (although it's not fool-proof!).
One more reason to not use Google-hosted jQuery is that in some countries, Google's domain name is banned.
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