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Getting key with maximum value in dictionary?
... I thought dict is unsorted, couldn't d.keys and d.values theoretically be ordered differently?
– Dimath
Apr 1 '15 at 13:28
1
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SQL - HAVING vs. WHERE
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First we should know the order of execution of Clauses i.e
FROM > WHERE > GROUP BY > HAVING > DISTINCT > SELECT > ORDER BY.
Since WHERE Clause gets executed before GROUP BY Clause the records cannot be filtered by applying WHERE to ...
Best way to build a Plugin system with Java
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First you need an interface that all plugins need to implement, e.g.
public interface Plugin {
public void load(PluginConfiguration pluginConfiguration);
public void run();
public void unload();
public JComponent getConfigurationPage();
}
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Non-CRUD operations in a RESTful service
...tually creating a new resource. So:
POST /api/purchase
will place a new order. The details (user, car, etc.) should be referenced by id (or URI) inside the contents sent to this address.
It doesn't matter that ordering a car is not just a simple INSERT in the database. Actually, REST is not abou...
Using LIMIT within GROUP BY to get N results per group?
...gregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
std::next_permutation Implementation Explanation
...nd the permutations as numbers. Viewing the problem in this way we want to order the permutations/numbers in "ascending" order.
When we order numbers we want to "increase them by the smallest amount". For example when counting we don't count 1, 2, 3, 10, ... because there are still 4, 5, ... in bet...
Android file chooser [closed]
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Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity.
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Encrypt Password in Configuration Files? [closed]
...simple way of doing this is to use Password Based Encryption in Java. This allows you to encrypt and decrypt a text by using a password.
This basically means initializing a javax.crypto.Cipher with algorithm "AES/CBC/PKCS5Padding" and getting a key from javax.crypto.SecretKeyFactory with the "PBKDF...
How to display unique records from a has_many through relationship?
...q option on the has_many association:
has_many :products, :through => :orders, :uniq => true
From the Rails documentation:
:uniq
If true, duplicates will be omitted from the collection. Useful in conjunction with :through.
UPDATE FOR RAILS 4:
In Rails 4, has_many :products, :thr...
Difference between “managed” and “unmanaged”
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Unmanaged code compiles straight to machine code. So, by that definition all code compiled by traditional C/C++ compilers is 'unmanaged code'. Also, since it compiles to machine code and not an intermediate language it is non-portable.
No free memory management or anything else the CLR provides.
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