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Insert into … values ( SELECT … FROM … )
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The documentation does list this (now?): this syntax is INSERT INTO ... VALUES ([expr], [expr], ...) and one of the paths in [expr] is {{NOT} EXISTS} ([select-stmt]) - note that the paranthesis around the select statement are required ({} meaning optional)
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How to count the number of occurrences of an element in a List
...ld always try composition rather than inheritance. Your implementation is now stuck to ArrayList when there may be times you want a LinkedList or other. Your example should have taken another LIst in its constructor/factory and returned a wrapper.
– mP.
Feb 5...
:active pseudo-class doesn't work in mobile safari
...-color: rgba(0,0,0,0);">
Testing Touch on iOS
</button>
Now when the button is tapped and held on iOS, the button changes to the specified color without the surrounding transparent gray color appearing.
In other words, setting an ontouchstart event (even if it's empty) is explic...
Concept of void pointer in C programming
...e a void* in two ways. Casting to char* is always acceptable, and if you know the original type it points to you can cast to that type. The void* has lost the type info so it'd have to be stored elsewhere.
– Dan Olson
Mar 29 '09 at 10:30
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GitHub authentication failing over https, returning wrong email address
... Credential Manager => Windows Manager
Delete everything related to tfs
Now click on Add a generic credential and provide the following values
(1) Internet or network adress: git:https://tfs.donamain name
(2) username: your username
(3) password: your password
this should fix it
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In git, what is the difference between merge --squash and rebase?
...of squash using --commit explicitly.
git/git builtin/merge.c#cmd_merge() now includes:
if (option_commit > 0)
die(_("You cannot combine --squash with --commit."));
git rebase --interactive
replays some or all of your commits on a new base, allowing you to squash (or more recently "f...
What is the recommended approach towards multi-tenant databases in MongoDB?
...o use a relational database. My data is quite unstructured, however, which now has me investigating NoSQL dbs like MongoDB. It doesn't seem that MongoDB have ACL support the way Lotus Domino does, and I don't really want to reinvent the wheel, which makes me also think 2 or 3 are the way to go. I a...
C# Interfaces. Implicit implementation versus Explicit implementation
...Explicit is when you define methods within your class on the interface. I know that sounds confusing but here is what I mean: IList.CopyTo would be implicitly implemented as:
public void CopyTo(Array array, int index)
{
throw new NotImplementedException();
}
and explicitly as:
void ICollecti...
What's a correct and good way to implement __hash__()?
...on, this is about as fast as any hash can be. Sure, if the attributes are known to be integers, and there aren't too many of them, I suppose you could potentially run slightly faster with some home-rolled hash, but it likely wouldn't be as well distributed. hash((self.attr_a, self.attr_b, self.attr_...
What is the benefit of using $() instead of backticks in shell scripts?
...> parent=$(basename $(dirname $PWD))
pax> echo $parent
xyzzy
(a) Now that specific command may not actually work, I haven't tested the functionality. So, if you vote me down for it, you've lost sight of the intent :-) It's meant just as an illustration as to how you can nest, not as a bug-...