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MySQL “Group By” and “Order By”
...olumns in a SELECT with a GROUP BY clause is non-standard. MySQL will generally return the values of the first row it finds and discard the rest. Any ORDER BY clauses will only apply to the returned column value, not to the discarded ones.
IMPORTANT UPDATE
Selecting non-aggregate columns used to wor...
What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...or example, we need to use one of our own methods in a query we would typically write something like
var query = context.Observations.Select(o => o.Id)
.AsEnumerable().Select(x => MySuperSmartMethod(x))
ToList – which converts an IEnumerable<T> to a List<T> ...
Can I set background image and opacity in the same property?
... Yeah, the big problem with a PNG is the size. It is likely going to be really large. Now that we can specify opacity: ... in all browsers, it way better!
– Alexis Wilke
Jul 1 '17 at 23:49
...
How to directly initialize a HashMap (in a literal way)?
...
All Versions
In case you happen to need just a single entry: There is Collections.singletonMap("key", "value").
For Java Version 9 or higher:
Yes, this is possible now. In Java 9 a couple of factory methods have been added...
git merge: apply changes to code that moved to a different file
...s copy has been done in a commit that we name commit CP.
You want to apply all your local changes, commits A and B below, that were made on original.txt, to the new file copy.txt.
---- X -----CP------ (master)
\
`--A---B--- (local)
Create a throwaway branch move at the starting p...
Can I split an already split hunk with git?
... discovered git's patch option to the add command, and I must say it really is a fantastic feature.
I also discovered that a large hunk could be split into smaller hunks by hitting the s key, which adds to the precision of the commit.
But what if I want even more precision, if the split hunk i...
Do spurious wakeups in Java actually happen?
...hread_cond_wait() function in Linux is implemented using the futex system call. Each blocking system call on Linux returns abruptly with EINTR when the process receives a signal. ... pthread_cond_wait() can't restart the waiting because it may miss a real wakeup in the little time it was outside the...
Are strongly-typed functions as parameters possible in TypeScript?
...f the types of its argument and its return type. Here we specify that the callback parameter's type must be "function that accepts a number and returns type any":
class Foo {
save(callback: (n: number) => any) : void {
callback(42);
}
}
var foo = new Foo();
var strCallback = (re...
What exactly does git rebase --skip do?
...lready existed upstream, Git will not be able to apply your commit (but usually should skip it automatically, if the patch is exactly the same). Your own commit will be skipped, but the change will still exist in current HEAD, because it was already applied upstream.
You should really make sure you...
How to check if a stored procedure exists before creating it
...uld do, but is not stored on the database side.
That's much like what is called anonymous procedure in PL/SQL.
Update:
Your question title is a little bit confusing.
If you only need to create a procedure if it not exists, then your code is just fine.
Here's what SSMS outputs in the create scri...