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When to use a View instead of a Table?

...ose facts from a certain client. Views for insertion/updates: You can handle security issues with views by using such functionality as Oracle's "WITH CHECK OPTION" clause directly in the view Drawbacks You lose information about relations (primary keys, foreign keys) It's not obvious whether...
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The model backing the context has changed since the database was created

... I've changed my production db manually and turned off the migration and it works, Thanks – Mohsen Afshin Sep 10 '12 at 21:05 13 ...
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How to fix .pch file missing on build?

...es, select All Configurations from the drop-down menu. Open the C/C++ tree and select Precompiled Headers Precompiled Header: Select Use (/Yu) Fill in the Precompiled Header File field. Standard is stdafx.h Click Okay If you do not have stdafx.h in your Header Files put it there. Edit it to #include...
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Analyze audio using Fast Fourier Transform

...you need to calculate the square root of the sum of the square of its real and imaginary components. That is, if your coefficient is a + b*j, then its magnitude is sqrt(a^2 + b^2). Once you have calculated the magnitude of each FFT coefficient, you need to figure out which audio frequency each FFT ...
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Is there a JavaScript MVC (micro-)framework? [closed]

... Skip Backbone and go right for Spine. It's got a much more logical MVC implementation. – Chris Jaynes May 19 '12 at 5:27 ...
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Disable Drag and Drop on HTML elements?

...ich is supposed to trigger a resize operation) the web browser gets clever and thinks I mean to drag and drop something. End result, my action gets put on hold while the browser does its drag and drop thing. ...
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes

I'm coming to Postgres from Oracle and looking for a way to find the table and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer. ...
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Lock, mutex, semaphore… what's the difference?

... A lock allows only one thread to enter the part that's locked and the lock is not shared with any other processes. A mutex is the same as a lock but it can be system wide (shared by multiple processes). A semaphore does the same as a mutex but allows x number of threads to enter, this...
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How to print like printf in Python3?

... In both versions, % is an operator which requires a string on the left-hand side and a value or a tuple of values or a mapping object (like dict) on the right-hand side. So, your line ought to look like this: print("a=%d,b=%d" % (f(x,n),g(x,n))) Also, the recommendation for Python3 and newer ...
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Convert PHP closing tag into comment

...enate the string from two pieces. This way, the closing tag is cut in two, and is not a valid closing tag anymore. '?>' --> '?'.'>' In your code: $string = preg_replace('#<br\s*/?'.'>(?:\s*<br\s*/?'.'>)+#i', '<br />', $string); This will make // comments work. For /*...