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Database development mistakes made by application developers [closed]
...Specifically, using a natural key will give you the ability to control the order in which data in your table is written to the disk. If you know how your table will be queried, you can index it so concurrently-accessed rows will end-up in the same page. Furthermore, you can enforce data integrity us...
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 ...
How to insert element into arrays at specific position?
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[3] => more
[4] => three
)
for the second one there is no order so you just have to do :
$array_2['more'] = '2.5';
print_r($array_2);
And sort the keys by whatever you want.
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How can I restore /etc/nginx? [closed]
By mistake I have removed /etc/nginx directory in my ubuntu 11.10 PC. How can I restore the ngnix directory in /etc/nginx ?
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How can I reverse a NSArray in Objective-C?
...rray with the objects that have not yet been traversed with nextObject, in order:
This array contains all the remaining objects of the enumerator in enumerated order.
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Why hasn't functional programming taken over yet?
...roductivity goes up (example: Erlang)
Productivity has to go up a lot in order to justify the massive expense of hiring programmers who know how to program in a functional style.
And remember, you don't want to throw away a working system; most programmers are not building new systems from scratc...
How can you determine how much disk space a particular MySQL table is taking up?
...ze_mb, table_name FROM information_schema.tables WHERE table_schema='mydb' order by tablesize_mb; to get a list of all tables of mydb with name and size, ordered by size.
– kqw
Jun 15 '15 at 18:03
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Ways to iterate over a list in Java
...dingly. There's no "copying" per-se, but because of the language design in order to make changes to the contents of e I'd have to call one of e's methods because assignment just changes the pointer (pardon my C).
– jacobq
Aug 23 '13 at 20:03
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how to get the one entry from hashmap without iterating
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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...
Get array of object's keys
...ys(foo);
console.log(keys) // ['alpha', 'beta']
// (or maybe some other order, keys are unordered).
This is an ES5 feature. This means it works in all modern browsers but will not work in legacy browsers.
The ES5-shim has a implementation of Object.keys you can steal
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