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Can a foreign key be NULL and/or duplicate?
...als. Suppose further that each proposal only has one sales person assigned and one client. So your proposal table would have two foreign keys, one with the client ID and one with the sales rep ID. However, at the time the record is created, a sales rep is not always assigned (because no one is fre...
Can every recursion be converted into iteration?
...u always turn a recursive function into an iterative one? Yes, absolutely, and the Church-Turing thesis proves it if memory serves. In lay terms, it states that what is computable by recursive functions is computable by an iterative model (such as the Turing machine) and vice versa. The thesis does ...
Can code that is valid in both C and C++ produce different behavior when compiled in each language?
C and C++ have many differences, and not all valid C code is valid C++ code.
(By "valid" I mean standard code with defined behavior, i.e. not implementation-specific/undefined/etc.)
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How can I delete a file from a Git repository?
...y. After that, I committed it, added a couple of directories called dir1 and dir2 , and committed them to the Git repository.
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Difference between return and exit in Bash functions
What is the difference between the return and exit statement in Bash functions with respect to exit codes?
10 Answers
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How do the post increment (i++) and pre increment (++i) operators work in Java?
...=>
i=5 + 7 + 8; (a=8)
The main point is that ++a increments the value and immediately returns it.
a++ also increments the value (in the background) but returns unchanged value of the variable - what looks like it is executed later.
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Is there any use for unique_ptr with array?
...ocators. Some people need a dynamically sized array, so std::array is out. And some people get their arrays from other code that is known to return an array; and that code isn't going to be rewritten to return a vector or something.
By allowing unique_ptr<T[]>, you service those needs.
In sh...
How do you use bcrypt for hashing passwords in PHP?
Every now and then I hear the advice "Use bcrypt for storing passwords in PHP, bcrypt rules".
11 Answers
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How can you do anything useful without mutable state?
I've been reading a lot of stuff about functional programming lately, and I can understand most of it, but the one thing I just can't wrap my head around is stateless coding. It seems to me that simplifying programming by removing mutable state is like "simplifying" a car by removing the dashboard:...
What is the leading LINQ for JavaScript library? [closed]
... really the same as linq to objects. (If it was, why would we need both Rx and Linq to Objects in .NET?) It works in the opposite direction to normal Linq in terms of the flow of data.
– Daniel Earwicker
Mar 23 '10 at 8:24
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