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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...
Set environment variables on Mac OS X Lion
... idea where these files are, how to create them if I have to do that, etc, and also why there seem to be so many different ones (why? Do they do different things?)
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Are the shift operators () arithmetic or logical in C?
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When shifting left, there is no difference between arithmetic and logical shift. When shifting right, the type of shift depends on the type of the value being shifted.
(As background for those readers unfamiliar with the difference, a "logical" right shift by 1 bit shifts all the bits ...
Combine two ActiveRecord::Relation objects
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If you want to combine using AND (intersection), use merge:
first_name_relation.merge(last_name_relation)
If you want to combine using OR (union), use or†:
first_name_relation.or(last_name_relation)
† Only in ActiveRecord 5+; for 4.2 install ...
What is a bank conflict? (Doing Cuda/OpenCL programming)
I have been reading the programming guide for CUDA and OpenCL, and I cannot figure out what a bank conflict is. They just sort of dive into how to solve the problem without elaborating on the subject itself. Can anybody help me understand it? I have no preference if the help is in the context of CUD...
What are the default access modifiers in C#?
...ult access modifier for classes, methods, members, constructors, delegates and interfaces?
9 Answers
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How to call a stored procedure from Java and JPA
I am writing a simple web application to call a stored procedure and retrieve some data.
Its a very simple application, which interacts with client's database. We pass employee id and company id and the stored procedure will return employee details.
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How to grep Git commit diffs or contents for a certain word?
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To illustrate the difference between -S<regex> --pickaxe-regex and -G<regex>, consider a commit with the following diff in the same file:
+ return !regexec(regexp, two->ptr, 1, &regmatch, 0);
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- hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);
While git ...
Extract file basename without path and extension in bash [duplicate]
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You don't have to call the external basename command. Instead, you could use the following commands:
$ s=/the/path/foo.txt
$ echo "${s##*/}"
foo.txt
$ s=${s##*/}
$ echo "${s%.txt}"
foo
$ echo "${s%.*}"
foo
Note that this solution should work in all recent (post 2004) POS...
Paging in a Rest Collection
... (think CouchDB or Persevere ). The problem I'm running into is how to handle the GET operation on the collection root if the collection is large.
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