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SQL select only rows with max value on a column [duplicate]
... timings relate to each other as 6/8/9, when it comes to direct lookups or batch (id in (1,2,3)), subquery is much slower then the others (Due to rerunning the subquery). However I couldnt differentiate between leftjoin and correlated solutions in speed.
One final note, as leftjoin creates n*(n+1)/...
console.writeline and System.out.println
...m)
synchronisation (multiple threads can prompt for input and Console will queue them up nicely, whereas if you used System.in/out then all of the prompts would appear simultaneously).
Notice above that redirecting even one of the streams results in System.console() returning null; another irritat...
Is String.Format as efficient as StringBuilder
...d when a user clicks a button now and again. Unless you're doing some huge batch processing job I'd stick with String.Format, it aids code readability. If you suspect a perf bottleneck then stick a profiler on your code and see where it really is.
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Persistence unit as RESOURCE_LOCAL or JTA?
...ral purpose transaction manager and can enlist other resources such as JMS queues in transaction. Typically Java EE containers employ a JTA transaction manager for EJBs, JPA entities, etc.
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What's is the difference between train, validation and test set, in neural networks?
...r surface will be different for different sets of data from your data set (batch learning). Therefore if you find a very good local minima for your test set data, that may not be a very good point, and may be a very bad point in the surface generated by some other set of data for the same problem. T...
Must qualify the allocation with an enclosing instance of type GeoLocation
...ExecutorService service = Executors.newFixedThreadPool(size);
// queue some tasks
for(int i = 0; i < 3 * size; i++) {
service.submit(new ThreadTask(i));
}
// wait for termination
service.shutdown();
service.awaitTermination(Lo...
Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
...ormal binary give would only release the thread at the head of the waiting queue (assuming there is one blocked).
– Tall Jeff
Jul 2 '19 at 8:34
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How do I fix a merge conflict due to removal of a file in a branch?
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@ideasman42 I have updated my answer to show a batch-delete solution.
– void.pointer
Mar 26 '19 at 18:53
1
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Check if pull needed in Git
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How can I use this in a (Ubuntu) batch file, so that I can run other commands just in the case this command shows that a pull is needed?
– Ulysses Alves
Jun 8 '16 at 13:40
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When is it practical to use Depth-First Search (DFS) vs Breadth-First Search (BFS)? [closed]
... like. This is something like Level Order Tree Traversal where we will use QUEUE with ITERATIVE approach (Mostly RECURSION will end up with DFS). The numbers represent the order in which the nodes are accessed in a BFS:
In a depth first search, you start at the root, and follow one of the branche...