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how to get the one entry from hashmap without iterating
...
Maps are not ordered, so there is no such thing as 'the first entry', and that's also why there is no get-by-index method on Map (or HashMap).
You could do this:
Map<String, String> map = ...; // wherever you get this from
// Ge...
Why no love for SQL? [closed]
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MarkJ: I remember that I reordered WHERE clauses to optimize queries in oracle. They where resolved from bottom to the top... terrible.
– Stefan Steinegger
Oct 29 '09 at 12:55
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Table Naming Dilemma: Singular vs. Plural Names [closed]
...will always have a singular one (with few exceptions like News).
Customer
Order
User
Status
News
Reason 3. (Aesthetic and Order). Specially in master-detail scenarios, this reads better, aligns better by name, and have more logical order (Master first, Detail second):
1.Order
2.OrderDetail
Compa...
File system that uses tags rather than folders?
...imic directory structure. For example in a tag based file system the path /etc/init.d will give all the files that are tagged with exactly two tags i.e 'etc' and 'init.d'. For files which are tagged with other tags as well as these two tags, their extra tags can appear as directories inside /etc/ini...
Java 8 Distinct by property
...ream().filter(distinctByKey(Person::getName))
Note that if the stream is ordered and is run in parallel, this will preserve an arbitrary element from among the duplicates, instead of the first one, as distinct() does.
(This is essentially the same as my answer to this question: Java Lambda Stream...
What is the best way to iterate over a dictionary?
...is completely undeserving of so many upvotes. A dictionary has no implicit order, so using .ElementAt in this context might lead to subtle bugs. Far more serious is Arturo's point above. You'll be iterating the dictionary dictionary.Count + 1 times leading to O(n^2) complexity for an operation that ...
Wrapping a C library in Python: C, Cython or ctypes?
...o C for you. Or, you can start rewriting parts of your C code in Cython in order to avoid calls and to specialise and tighten your loops algorithmically. And if you need a fast callback, just write a function with the appropriate signature and pass it into the C callback registry directly. Again, no...
How to return result of a SELECT inside a function in PostgreSQL?
...pe = 'ALPHABETIC'
LIMIT _max_tokens
) t
GROUP BY t.txt
ORDER BY cnt DESC; -- potential ambiguity
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM word_frequency(123);
Explanation:
It is much more practical to explicitly define the return type than sim...
Resizing an iframe based on content
...izePipe()">
<iframe id="helpframe" src='' height='0' width='0' frameborder='0'></iframe>
<script type="text/javascript">
function iframeResizePipe()
{
// What's the page height?
var height = document.body.scrollHeight;
// Going to 'pipe' the data to the pare...
windows service vs scheduled task
...dly prototyping", as my IT Dept often does, you do whatever you have to in order to make ends meet. Once the prototyping and proof of concept stuff is out of the way, usually in the early planning and discovering, you have to decide what's more reliable for long term sustainability.
OK, so in concl...