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How to encrypt/decrypt data in php?
... = openssl_random_pseudo_bytes(openssl_cipher_iv_length("AES-256-CBC")) in order to indicate the link between iv's size to use with the cipher used. You could also expand a bit on the need (or not) of pkcs7_pad()/pkcs7_unpad(), or just simplify the post by getting rid of them and use "aes-256-ctr". ...
How does HashSet compare elements for equality?
...y the default equality comparer.
Note how none of this is in terms of an ordered comparison - which makes sense, as there are certainly situations where you can easily specify equality but not a total ordering. This is all the same as Dictionary<TKey, TValue>, basically.
If you want a set w...
How to convert an NSString into an NSNumber
...r of any primitive data type (e.g. int , float , char , unsigned int , etc.)? The problem is, I don't know which number type the string will contain at runtime.
...
Select Row number in postgres
...
You should also specify an order in OVER clause: OVER (ORDER BY id). Otherwise the order is not guaranteed.
– AlexM
Jun 14 '16 at 4:30
...
Is Java “pass-by-reference” or “pass-by-value”?
...e get to the Java implementation:
Values go on and off the stack in a nice orderly fashion, like a stack of plates at a cafeteria.
Memory in the heap (also known as dynamic memory) is haphazard and disorganized. The JVM just finds space wherever it can, and frees it up as the variables that use it a...
generate days from date range
...ECT
date
FROM
dates
WHERE
date BETWEEN '2010-01-20' AND '2010-01-24'
ORDER BY
date
Update
It is worth noting that you will only be able to generate past dates starting from the current date. If you want to generate any kind of dates range (past, future, and in between), you will have to u...
HEAD and ORIG_HEAD in Git
...anch". that's why when you in detached head , you do git branch foo -b in order to "create" a branch for that orphans commits.
– Royi Namir
Mar 11 '19 at 11:41
add a comment
...
How to get a random value from dictionary in python
...b': 5}
>>> d.popitem()
('c', 7)
Since the dict doesn't preserve order, by using popitem you get items in an arbitrary (but not strictly random) order from it.
Also keep in mind that popitem removes the key-value pair from dictionary, as stated in the docs.
popitem() is useful to dest...
What are some uses of template template parameters?
...drei Alexandrescu:
He uses a classes with template template parameters in order to implement the policy pattern:
// Library code
template <template <class> class CreationPolicy>
class WidgetManager : public CreationPolicy<Widget>
{
...
};
He explains:
Typically, the host cla...
Locate the nginx.conf file my nginx is actually using
...default nginx config file path.
$ nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
$ nginx -V
nginx version: nginx/1.11.1
built by gcc 4.9.2 (Debian 4.9.2-10)
built with OpenSSL 1.0.1k 8 Jan 2015
TLS SNI su...