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Delete everything in a MongoDB database
...way everything in a database—that is, to delete every single collection, and whatever else might be lying around, and start from scratch. Is there a single line of code that will let me do this? Bonus points for giving both a MongoDB console method and a MongoDB Ruby driver method.
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switch case statement error: case expressions must be constant expression
...ning eclipse gave me an error underlining the case statements in color red and says: case expressions must be constant expression, it is constant I don't know what happened. Here's my code below:
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Error: allowDefinition='MachineToApplication' beyond application level
...he most recent build I had was Debug. I opened the solution, did a bug fix and attempted to build in RRelease mode. Cleaning in Release didn't work but cleaning in Debug did. (Probably a combo of the 2 was what was needed, i.e. clear out any old refs to dlls, whether Debug or Release).
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How to convert a string into double and vice versa?
I want to convert a string into a double and after doing some math on it, convert it back to a string.
12 Answers
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What are the use cases for selecting CHAR over VARCHAR in SQL?
...R(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the same length (within two characters length difference).
Note: Microsoft SQL has 2 bytes of overhead for a VARCHAR. This may vary from DB to DB, but generally, there is at lea...
How do I create test and train samples from one dataframe with pandas?
I have a fairly large dataset in the form of a dataframe and I was wondering how I would be able to split the dataframe into two random samples (80% and 20%) for training and testing.
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What are the differences in die() and exit() in PHP?
What are the differences between die() and exit() functions in PHP?
16 Answers
16
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Targeting .NET Framework 4.5 via Visual Studio 2010
... Studio 2010. Unfortunately I am not, even manually removing certain 4.0 and adding the corresponding 4.5 assemblies resulted in the original 4.0 assemblies still being referenced in the project.
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write a shell script to ssh to a remote machine and execute commands
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There are multiple remote linux machines, and I need to write a shell script which will execute the same set of commands in each machine. (Including some sudo operations). How can this be done using shell scripting?
You can do this with ssh, for example:
#!/bin/ba...
How to fix error “Updating Maven Project”. Unsupported IClasspathEntry kind=4?
...ue has been fixed in m2e 1.5.0 which is available for Eclipse Kepler (4.3) and Luna (4.4)
Please see https://bugs.eclipse.org/bugs/show_bug.cgi?id=374332#c14
The problem is caused by the fact that STS (the Spring IDE/Eclipse), as well Eclipse and other Eclipse based IDE's, use the m2e(clipse) plug...