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Double vs single quotes
I'm really new to Ruby and I'm trying to understand if there's a specific time when I should use "" vs '' .
8 Answers
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How can I cast int to enum?
... (e.g. "2342342" -- assuming that's not a value of your enum), it will actually allow that without throwing an error! Your enum will have that value (2342342) even though it's not a valid choice in the enum itself.
– JoeCool
Jun 25 '13 at 15:14
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SQL JOIN - WHERE clause vs. ON clause
...der and its lines, if any, for order number 12345. The second will return all orders, but only order 12345 will have any lines associated with it.
With an INNER JOIN, the clauses are effectively equivalent. However, just because they are functionally the same, in that they produce the same results...
MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
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I think the extension is intended to allow a similar syntax for inserts and updates. In Oracle, a similar syntactical trick is:
UPDATE table SET (col1, col2) = (SELECT val1, val2 FROM dual)
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Method Resolution Order (MRO) in new-style classes?
...ject'>)
with A forced to come in resolution order only once and after all of its subclasses, so that overrides (i.e., C's override of member x) actually work sensibly.
It's one of the reasons that old-style classes should be avoided: multiple inheritance with "diamond-like" patterns just doesn...
Visual Studio: Is there a way to collapse all items of Solution Explorer?
...xplorer one by one, but I would like to know if there is a way to collapse all items with only one operation. I want to know it because, today I have a solution with 6 projects that have at least two hundred files and if I try to collapse them one-by-one I will have a hard time.
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Loader lock error
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If I run the project as Native debugging, with all exceptions on default (reset all), the debug window shows <mda:msg xmlns:mda="schemas.microsoft.com/CLR/2004/10/mda"> <!-- Attempting managed execution inside OS Loader lock.... etc --> <mda...
Benefits of EBS vs. instance-store (and vice-versa) [closed]
...re's why
EBS backed instances can be set so that they cannot be (accidentally) terminated through the API.
EBS backed instances can be stopped when you're not using them and resumed when you need them again (like pausing a Virtual PC), at least with my usage patterns saving much more money than I ...
Which version of C# am I using
... does not tell you the right version number - on my PC, .NET 4.6 RC is installed but Assembly.ImageRuntimeVersion reports v4.0.30319
– Matt
Jul 14 '15 at 10:55
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Unable to start debugging because the object invoked has disconnected from its clients
...e control engine
Review the list of extensions and plugins. Try to disable all or some of them
Close Visual Studio and kill all the development processes: devenv, mspdbsrv, vcpkgsrv, msbuild, msvsmon, vshub, vstest etc
Remove .suo, .ncb, .VC.db, .VC.VC.opendb files of the solution as well as .vs dir...