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Hidden Features of MySQL
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Since you put up a bounty, I'll share my hard won secrets...
In general, all the SQLs I tuned today required using sub-queries. Having come from Oracle database world, things I took for granted weren’t working the same with MySQL. And my reading on MySQL tuning makes me conclude that MySQL is be...
Do Facebook Oauth 2.0 Access Tokens Expire?
...ays, when the person using your app makes a request to Facebook's servers.
All access tokens need to be renewed every 90 days with the consent of the person using your app.
Facebook change announce (10/04/2018)
Facebook updated token expiration page (10/04/2018)
offline_access:
Enables your a...
What's the best way to set a single pixel in an HTML5 canvas?
... as an exercise for the reader
creating another img or canvas filled with all the pixels you want and use drawImage() to blit just the pixel you want across. This would probably be very fast, but has the limitation that you need to pre-calculate the pixels you need.
Note that my tests do not atte...
Remove elements from collection while iterating
...61-4")));
Collect and Remove
The first technique consists in collecting all the objects that we want to delete (e.g. using an enhanced for loop) and after we finish iterating, we remove all found objects.
ISBN isbn = new ISBN("0-201-63361-2");
List<Book> found = new ArrayList<Book>()...
What happens when a computer program runs?
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It really depends on the system, but modern OSes with virtual memory tend to load their process images and allocate memory something like this:
+---------+
| stack | function-local variables, return addresses, return values, e...
What is the difference between “int” and “uint” / “long” and “ulong”?
...128 to 127. The 9th bit represents 256. So with 8 bits you can represent all values up to 255 (9th val - 1). The range from -128 to 127 has a length of exactly 255. So there is no bit that holds the sign. All values up to 127 are positive. Values above get displayed negative. 255 would be -1. 254 wo...
How do I reset the scale/zoom of a web app on an orientation change on the iPhone?
... the landscape mode I have to double tap on something twice, first to zoom all the way in (the normal double tap behavior) and again to zoom all the way out (again, the normal double tap behavior). When it zooms out, it zooms out to the correct NEW scale for landscape mode.
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Update relationships when saving changes of EF4 POCO objects
...ost to context. After attaching object to context the state of the object, all related objects and all relations is set to Unchanged.
Use context.ObjectStateManager.ChangeObjectState to set your BlogPost to Modified
Iterate through Tag collection
Use context.ObjectStateManager.ChangeRelationshipStat...
Unignore subdirectories of ignored directories in Git
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I have a global gitignore file where I ignored all *.zip file. Yet for a particular project, I want to include zip files. I added this line to that project's .gitignore and it works great!: !*.zip
– Jinghao Shi
Mar 21 '15 at 3:44
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How does the main() method work in C?
...d nothing bad happens with their given compiler.
This is the case if the calling conventions are such that:
The calling function cleans up the arguments.
The leftmost arguments are closer to the top of the stack, or to the base of the stack frame, so that spurious arguments do not invalidate the ...