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Can a foreign key be NULL and/or duplicate?
...inition. 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 tab...
Function passed as template argument
...cout << "Result is " << temp << std::endl;
}
which can now be called as either:
doOperation(add2);
doOperation(add3());
See it live
The problem with this is that if it makes it tricky for the compiler to inline the call to add2, since all the compiler knows is that a function...
Heap vs Binary Search Tree (BST)
...s for individual inserts.
Interpretation:
heap is still constant, but now we see in more detail that there are a few lines, and each higher line is more sparse.
This must correspond to memory access latencies are done for higher and higher inserts.
TODO I can't really interpret the BST fully o...
`require': no such file to load — mkmf (LoadError)
...
This is also required for aws-sdk now that SOAP is deprecated for AWS. A worry if stakeholders object to anything -dev on a production build. (SDK's don't thrill them either).
– mckenzm
Dec 20 '14 at 20:47
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Eclipse error: “The import XXX cannot be resolved”
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This bug is now at least 9 years old.
– user1133275
Mar 28 '19 at 16:40
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How to convert a string of numbers to an array of numbers?
...ature of split function) but it is equivalent to split(','). The string is now an array, we just have to map each value with a function returning the integer of the string so x=>+x (which is even shorter than the Number function (5 chars instead of 6)) is equivalent to :
function(x){return parse...
Difference between CouchDB and Couchbase
... is still CouchDB, actively maintained and enhanced as an Apache project.
Now to the relevant differences:
Licensing
The Couchbase Server is not entirely open-source/free software. There are two versions: Community Edition (free but no latest bug fixes) and Enterprise Edition (there are restricti...
The following sections have been defined but have not been rendered for the layout page “~/Views/Sha
...al") } So i deleted those for the time being and everything is working for now.
– Kevin Dark
Jun 11 '12 at 4:08
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How to redirect both stdout and stderr to a file [duplicate]
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&> now works as expected on OS X 10.11.1 (seems to be bash 3.2), just for the record.
– LiberalArtist
Nov 28 '15 at 20:32
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How to update column with null value
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Now, let me clarify. Through php I am using PDO and updating through a query.
– jim
Oct 6 '10 at 8:13
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