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Mongod complains that there is no /data/db folder
..., e.g. sudo mkdir -p /data/db
Or you need to do su - to become superuser, and then create the directory with mkdir -p /data/db
Note:
MongoDB also has an option where you can create the data directory in another location, but that's generally not a good idea, because it just slightly complicate...
OO Design in Rails: Where to put stuff
I'm really enjoying Rails (even though I'm generally RESTless), and I enjoy Ruby being very OO. Still, the tendency to make huge ActiveRecord subclasses and huge controllers is quite natural (even if you do use a controller per resource). If you were to create deeper object worlds, where would you p...
The located assembly's manifest definition does not match the assembly reference
...un some unit tests in a C# Windows Forms application (Visual Studio 2005), and I get the following error:
53 Answers
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Boolean vs boolean in Java
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Yes you can use Boolean/boolean instead.
First one is Object and second one is primitive type.
On first one, you will get more methods which will be useful.
Second one is cheap considering memory expense The second will save you a lot more memory, so go for it
Now choose your way....
How to exit from PostgreSQL command line utility: psql
What command or short key can I use to exit the PostgreSQL command line utility psql ?
9 Answers
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Is a url query parameter valid if it has no value?
...ikely acceptable to your server-side framework/code
The URI RFC doesn't mandate a format for the query string. Although it is recognized that the query string will often carry name-value pairs, it is not required to (e.g. it will often contain another URI).
3.4. Query
The query componen...
Popstate on page's load in Chrome
I am using History API for my web app and have one issue.
I do Ajax calls to update some results on the page and use history.pushState() in order to update the browser's location bar without page reload. Then, of course, I use window.popstate in order to restore previous state when back-button i...
How to make lists contain only distinct element in Python? [duplicate]
...g aspect of this new implementation is considered an implementation detail and should not be relied upon". Since they're both based on hashes, I'd think set would be the same, but it's not mentioned, so apparently not: docs.python.org/3.6/whatsnew/3.6.html
– Mark
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Google Gson - deserialize list object? (generic type)
...n<...>() {}.getType() captures a compile-time type (between the < and >) into a runtime java.lang.reflect.Type object. Unlike a Class object, which can only represent a raw (erased) type, the Type object can represent any type in the Java language, including a parameterized instantiation...
How does BLAS get such extreme performance?
...k The Science of Programming Matrix Computations by Robert A. van de Geijn and Enrique S. Quintana-Ortí. They provide a free download version.
BLAS is divided into three levels:
Level 1 defines a set of linear algebra functions that operate on vectors only. These functions benefit from vectoriza...