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What are the disadvantages of using persistent connection in PDO
...ase connections as the one thing that is a bottleneck in your script (this means you've done code profiling using xdebug and/or xhprof), you should not consider persistent connections as a solution to anything.
Further, most modern databases (including PostgreSQL) have their own preferred ways of p...
The role of #ifdef and #ifndef
... left in or removed by the pre-processor depending on the condition. ifdef means "if the following is defined" while ifndef means "if the following is not defined".
So:
#define one 0
#ifdef one
printf("one is defined ");
#endif
#ifndef one
printf("one is not defined ");
#endif
is equival...
How do JavaScript closures work?
...in JavaScript can be passed around like variables (first-class functions), meaning these pairings of functionality and state can be passed around your program: similar to how you might pass an instance of a class around in C++.
If JavaScript did not have closures, then more state would have to be pa...
Renew Provisioning Profile
... I don't have a renew button next to my expired profile. What does that mean? How do I renew it?
– MikeN
Mar 25 '11 at 0:27
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Shared-memory objects in multiprocessing
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Just to note, on Python fork() actually means copy on access (because just accessing the object will change its ref-count).
– Fabio Zadrozny
Jun 7 '12 at 17:30
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How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar
...y path and cache name if appropriate.
// nil for section name key path means "no sections".
NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest
...
How to send a “multipart/form-data” with requests in python?
...orm-data request but are not including any files, you can set a truthy but meaningless value such as {'':''}, and set data= with your request body. If you are doing this, don't provide the Content-Type header yourself; requests will set it for you. You can see the truth check here: github.com/psf/r...
CSS to make HTML page footer stay at bottom of the page with a minimum height, but not overlap the p
... class has a min-height value that depends on the viewport's height (100vh means 100% of the viewport height) and the footer's height, that I already knew was 40px.
That's all I did, and it worked perfectly for me. I haven't tried it in every browser, just Firefox, Chrome and Edge, and the results ...
E11000 duplicate key error index in mongodb mongoose
...tify people uniquely based on both their phone numbers and email - so this means that both the phone number and the email must be unique for every person.
However , there is a problem : I have realized that everyone has a phonenumber but not everyone has an email address .
Those that don`t have a...
What is the difference between Trap and Interrupt?
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What do you mean, "a bit confusing"? It's very confusing :-) The problem here is that divide by zero is a hardware interrupt (IRQ/vector 0) but the kernel developers have several choices how to handle it. So from a user process, it's a t...