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Can a foreign key be NULL and/or duplicate?
...ion. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you have a database that stores sales proposals. Suppose further that each proposal only has one sales person assigned and one client. So your proposal table w...
Closing Database Connections in Java
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@BalusC: Can u please explain what happens when a pooled connection is closed by using connection.close() method
– Krsna Chaitanya
Jan 10 '13 at 6:56
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Why do most fields (class members) in Android tutorial start with `m`?
I know about camel case rules, but I'm confused with this m rule. What does it stand for? I'm a PHP developer. "We" use first letters of variables as indication of type, like 'b' for boolean, 'i' for integer and so on.
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Is there any use for unique_ptr with array?
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@NoSenseEtAl: I'm not sure what part of "some people aren't allowed to do that" eludes you. Some projects have very specific requirements, and among them may be "you don't get to use vector". You can argue whether those are reasonable requirements or n...
Is there a unique Android device ID?
Do Android devices have a unique ID, and if so, what is a simple way to access it using Java?
52 Answers
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How to set time delay in javascript
...en after setTimeout finally it alerts I am setTimeout after 1sec (1000ms)
What you can notice from the example is that the setTimeout(...) is asynchronous which means it doesn't wait for the timer to get elapsed before going to next statement i.e alert("after setTimeout");
Example:
setInterval
a...
Exporting functions from a DLL with dllexport
...de C++, see the second section below.
Exporting/Importing DLL Libs in VC++
What you really want to do is define a conditional macro in a header that will be included in all of the source files in your DLL project:
#ifdef LIBRARY_EXPORTS
# define LIBRARY_API __declspec(dllexport)
#else
# define...
Why does DEBUG=False setting make my django Static Files Access fail?
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can someone tell me though what is so insecure about this
– Kavi Vaidya
Nov 20 '18 at 19:40
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How does Apple find dates, times and addresses in emails?
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el chief, in your opinion, what kind of model would be best for that? Bayesian?
– Martin
Feb 20 '12 at 2:21
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What is the meaning of the term arena in relation to memory?
... is very specialized and generally only comes in handy if you know exactly what you're doing and why the normal library allocation is not good enough. Note that a good memory allocator will already do lots of magic itself, and you need a decent amount of evidence that that's not good enough before y...