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Oracle TNS names not showing when adding new connection to SQL Developer

... line: echo %TNS_ADMIN% From linux: echo $TNS_ADMIN Restart SQL Developer Now in SQL Developer right click on Connections and select New Connection.... Select TNS as connection type in the drop down box. Your entries from tnsnames.ora should now display here. ...
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What are the use cases of Graph-based Databases (http://neo4j.org/)? [closed]

... We've been working with the Neo team for over a year now and have been very happy. We model scholarly artifacts and their relationships, which is spot on for a graph db, and run recommendation algorithms over the network. If you are already working in Java, I think that modeli...
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this.setState isn't merging states as I would expect

...ability helpers were recently added to React.addons, so with that, you can now do something like: var newState = React.addons.update(this.state, { selected: { name: { $set: 'Barfoo' } } }); this.setState(newState); Immutability helpers documentation. ...
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Are list-comprehensions and functional functions faster than “for loops”?

...specifically about map(), filter() and reduce(), but I assume you want to know about functional programming in general. Having tested this myself on the problem of computing distances between all points within a set of points, functional programming (using the starmap function from the built-in iter...
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Alternatives to gprof [closed]

...s still a bottleneck, but program counter sampling will not see it because now the hotspot is in string-compare. On the other hand if it were to sample the extended program counter (the call stack), the point at which the string-compare is called, the sort loop, is clearly displayed. In fact, gprof ...
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How fast is D compared to C++?

... @CyberShadow Thanks! With these flags runtime improves considerably. Now D is at 12.9 s. But still runs more than 3 times as long. @Matthieu M. I would not mind to test a program with boundschecking in slow motion and once it is debugged let it do its computations without boundschecking. (I do...
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How many and which are the uses of “const” in C++?

...ect remain the same. Once one of the object changes data, you however need now two versions: One for the original, and one for the copy. That is, you copy on a write to either object, so that they now both have their own version. Using code: int main() { string const a = "1234"; string co...
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Left Align Cells in UICollectionView

... the array. You may look into the source code for its implementation.) So now the only thing we have to do is to implement the layoutAttributesForItem(at indexPath: IndexPath) function properly. The super class UICollectionViewFlowLayout already puts the correct number of cells in each line so we o...
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Why dict.get(key) instead of dict[key]?

...ents anywhere? As mentioned here, It seems that all three approaches now exhibit similar performance (within about 10% of each other), more or less independent of the properties of the list of words. Earlier get was considerably slower, However now the speed is almost comparable along with t...
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Clustered vs Non-Clustered

My lower level knowledge of SQL (Server 2008) is limited, and is now being challanged by our DBAs. Let me explain (I have mentioned obvious statements in the hope that I am right, but if you see something wrong, please tell me) the scenario: ...