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What's the difference between VARCHAR and CHAR?
...CHAR(10),
Street VARCHAR(10));
Insert into temp
values('Pune','Oxford');
select length(city), length(street) from temp;
Output will be
length(City) Length(street)
10 6
Conclusion: To use storage space efficiently must use VARCHAR Instead CHAR if variable length is ...
How do I get only directories using Get-ChildItem?
...eturned by Get-ChildItem has a "base" property, PSIsContainer. You want to select only those items.
Get-ChildItem -Recurse | ?{ $_.PSIsContainer }
If you want the raw string names of the directories, you can do
Get-ChildItem -Recurse | ?{ $_.PSIsContainer } | Select-Object FullName
For PowerSh...
Pandas every nth row
...] # Excludes every 3rd row starting from 0
df2 = df[df.index % 3 == 0] # Selects every 3rd raw starting from 0
This arithmetic based sampling has the ability to enable even more complex row-selections.
This assumes, of course, that you have an index column of ordered, consecutive, integers star...
Difference between 'new operator' and 'operator new'?
...'s a good question in any case.
Operator new is a function that allocates raw memory -- at least conceptually, it's not much different from malloc(). Though it's fairly unusual unless you're writing something like your own container, you can call operator new directly, like:
char *x = static_cast&...
How do I change the language of moment.js?
...ng to change the language of the date which is being set by moment.js. The default one is English, but I want to set the German language. These is what I tried:
...
WebRTC - scalable live stream broadcasting / multicasting
...
You're actually explaining how an SFU (Selective Forwarding Unit) works. You can do the same with mediasoup
– Dirk V
Jun 17 at 13:16
add a ...
How do I sort unicode strings alphabetically in Python?
...just wanted to point out one coding inefficiency in Human Sort. To apply a selective char-by-char translation to a unicode string s, it uses the code:
spec_dict = {'Å':'A', 'Ä':'A'}
def spec_order(s):
return ''.join([spec_dict.get(ch, ch) for ch in s])
Python has a much better, faster and ...
Redis key naming conventions?
...e: always ensure that user is able to access only things you intended. The raw URL-to-key approach above is able to fetch user/1/password as well, as noted by commentators. This should not be a problem if you use Redis as a public read-only cache.
...
How to add custom method to Spring Data JPA
... public List<MyEntity> doSomeHql(Long id) {
String hql = "SELECT eFROM MyEntity e WHERE e.id = :id";
TypedQuery<MyEntity> query = entityManager.createQuery(hql, MyEntity.class);
query.setParameter("id", id);
return query.getResultList();
}
@Sup...
Pointers, smart pointers or shared pointers? [duplicate]
...hat it is in charge of deleteing it at some point. They allow you to get a raw reference to the pointer they wrap for passing to other methods, as well as releasing the pointer, allowing someone else to own it. Copying them does not make sense.
Shared pointers is a stack-allocated object that wraps ...