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MySQL, better to insert NULL or empty string?
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but which one you think is faster? 0 or NULL or ""
– Atul Dravid
Oct 16 '10 at 23:48
8
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General suggestions for debugging in R
...function you would find useful to have run.
And another two methods from one of @Shane's links:
Wrap an inner function call with try() to return more information on it.
For *apply functions, use .inform=TRUE (from the plyr package) as an option to the apply command
@JoshuaUlrich also pointed o...
Difference between add(), replace(), and addToBackStack()
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Can a fragment container contains more than one fragment, If yes than how replace() method will behave. WIll it replace all the frgaments in that container or android api have a method that accept three arguments, i.e. frgamentContainer, new fragment and with whom to r...
Best practices for storing postal addresses in a database (RDBMS)?
...and lots of pros and cons to each to be evaluated -- surely this has been done time and time again? Maybe someone has at least written done some lessons learned somewhere?
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Do AJAX requests retain PHP Session info?
...most comment there) is a separate question, let's now stick to the current one, with just one side-note: the most prominent issue with URL-based sessions -- the blatant visibility of the naked session ID -- is not an issue with internal Ajax calls; but then, if it's turned on for Ajax, it's turned o...
When to use a View instead of a Table?
... store the "view" temporarily in another table for faster access. This is done to speed up read access when the view is complex. But that doesn't help you in your case because a materialized view is still a view, not data on its own. Your approach is probably OK.
– Lukas Eder
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When to call activity context OR application context?
... prefer static data members, if for no other reason than you can only have one custom Application object. I built one app using a custom Application object and found it to be painful. Ms. Hackborn also agrees with this position.
Here are reasons why not to use getApplicationContext() wherever you g...
How to create a directory if it doesn't exist using Node.js?
...tice but probably won't cause any performance issue, but its a bad habbit none-the-less. Only use for booting your app or otherwise one time operations.
– tsturzl
Aug 14 '15 at 0:53
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How can one use multi threading in PHP applications
Is there a realistic way of implementing a multi-threaded model in PHP whether truly, or just simulating it. Some time back it was suggested that you could force the operating system to load another instance of the PHP executable and handle other simultaneous processes.
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What did MongoDB not being ACID compliant before v4 really mean?
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One thing you lose with MongoDB is multi-collection (table) transactions. Atomic modifiers in MongoDB can only work against a single document.
If you need to remove an item from inventory and add it to someone's order at th...