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Collection that allows only unique items in .NET?
...at contains no duplicate elements, and whose elements are in no particular order.
Note that the HashSet<T>.Add(T item) method returns a bool -- true if the item was added to the collection; false if the item was already present.
...
'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine
...application.
If you have built your project under x86 platform, then in order to
resolve you issue you should install the following packages on your
machine:
In order to use the 'Microsoft.ACE.OLEDB.12.0' provider you must
install the Microsoft Access Database Engine 2010 Redistributable
first...
Why can't I use the 'await' operator within the body of a lock statement?
...d resumes. That arbitrary code could be taking out locks that produce lock ordering inversions, and therefore deadlocks.
Worse, the code could resume on another thread (in advanced scenarios; normally you pick up again on the thread that did the await, but not necessarily) in which case the unlock ...
How do I find duplicate values in a table in Oracle?
...= oed.deptid )
group by oed.empid having count(oed.empid) > 1 order by count(oed.empid);
and if such table has primary key then use primary key instead of rowid, e.g id is pk then
select oed.empid, count(oed.empid)
from emp_dept oed
where exists ( select *
from emp...
SQL - Rounding off to 2 decimal places
...
Seems to convert to string ? which screws up order by.
– blissweb
Mar 4 '18 at 2:08
2
...
Git: how to reverse-merge a commit?
...it show <merge commit SHA1> to see the parents, the numbering is the order they appear e.g. Merge: e4c54b3 4725ad2
git merge documentation:
http://schacon.github.com/git/git-merge.html
git merge discussion (confusing but very detailed):
http://schacon.github.com/git/howto/revert-a-faulty-me...
Detect when a window is resized using JavaScript ?
... ", window.innerWidth, "px");
}
window.onresize = resize;
<p>In order for this code snippet to work as intended, you will need to either shrink your browser window down to the size of this code snippet, or fullscreen this code snippet and resize from there.</p>
...
How to access the ith column of a NumPy multidimensional array?
...columns, it could be a good idea to create our array in column-major ('F') order instead of the row-major ('C') order (which is the default), and then do the slicing as before to get a column without copying it:
A = np.asfortranarray(A) # or np.array(A, order='F')
A_c1_ref = A[:, 1]
A_c1_ref.strid...
Why do I have to access template base class members through the this pointer?
...
Short answer: in order to make x a dependent name, so that lookup is deferred until the template parameter is known.
Long answer: when a compiler sees a template, it is supposed to perform certain checks immediately, without seeing the templ...
Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
...nificant practical reason is that it forces the user to magically know the order in which columns will be returned. It's better to be explicit, which also protects you against the table changing, which segues nicely into...
If a column name you're using changes, it's better to catch it early (at the...