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SQLite add Primary Key
... pkName ON tableName(columnName)) when DB frameworks like MS SQL's SMO actually make you add a PK after the table has been created!
– SteveCinq
Aug 31 '17 at 18:06
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In C/C++ what's the simplest way to reverse the order of bits in a byte?
...b;
}
First the left four bits are swapped with the right four bits. Then all adjacent pairs are swapped and then all adjacent single bits. This results in a reversed order.
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Difference between C++03 throw() specifier C++11 noexcept
...Exception specifiers were deprecated because exception specifiers are generally a terrible idea. noexcept was added because it's the one reasonably useful use of an exception specifier: knowing when a function won't throw an exception. Thus it becomes a binary choice: functions that will throw and f...
Rails: How can I set default values in ActiveRecord?
...of the available methods, but I believe that defining an after_initialize callback is the way to go for the following reasons:
default_scope will initialize values for new models, but then that will become the scope on which you find the model. If you just want to initialize some numbers to 0 then...
What is a handle in C++?
I have been told that a handle is sort of a pointer, but not, and that it allows you to keep a reference to an object, rather than the object itself. What is a more elaborate explanation?
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Assign variable in if condition statement, good practice or not? [closed]
...tended to write this:
if (value == someFunction()) {
...
}
If you really want to do the assignment in place, I would recommend doing an explicit comparison as well:
if ((value = someFunction()) === <whatever truthy value you are expecting>) {
...
}
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What is the proper way to check if a string is empty in Perl?
... situation where you haven't already guarded against undef, then the catch-all for "non-empty" that won't warn is if (defined $str and length $str).
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push_back vs emplace_back
...h_back(Type&& _Val).
But the real C++0x form of emplace_back is really useful: void emplace_back(Args&&...);
Instead of taking a value_type it takes a variadic list of arguments, so that means that you can now perfectly forward the arguments and construct directly an object into a ...
How to calculate age (in years) based on Date of Birth and getDate()
...ated method does not have the issue with leap years, I'd suggest (if you really want to keep it at all) to move it down the bottom of your answer.
– ajbeaven
Jul 4 '17 at 23:14
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How to change the default GCC compiler in Ubuntu?
I have installed gcc-3.3/g++-3.3 on ubuntu 11.04 which already has gcc/g++-4.4. So in my system both gcc-3.3 and 4.4 are available. I am able to call both compilers as I want. If I just call the command gcc then gcc-4.4 will get called. To call gcc-3.3, I have to use the command gcc-3.3 .
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