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What is the difference between char * const and const char *?
... C-only, sorry for the C++ code link, I got here from a C++ question) It's all about the C declaration syntax, with a ("pure") type part followed by a declarator. In "int const *foo, *volatile bar" the type part is int const (stops before the *) and the declarators are *foo (the expression *foo will...
Rails “validates_uniqueness_of” Case Sensitivity
... 3rd Edition:
...despite its name, validates_uniqueness_of doesn’t really guarantee that column values will be unique. All it can do is verify that no column has the same value as that in the record being validated at the time the validation is performed. It’s possible for two records to be ...
How can I get the full object in Node.js's console.log(), rather than '[Object]'?
...console.log(obj) it still prints [Object] for deeply nested objects :( I really wish it would behave as you describe.
– SSH This
Feb 23 '16 at 22:36
53
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C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
Can the Android drawable directory contain subdirectories?
In the Android SDK documentation, all of the examples used with the @drawable/my_image xml syntax directly address images that are stored in the res/drawable directory in my project.
...
Ideal Ruby project structure
...pname folder because most libraries are in the appname namespace.
Additionally, if you try running the command newgem --simple [projectname] that'll quickly generate a scaffold for you with just the bare essentials for a Ruby project (and by extension a Ruby Gem). There are other tools which do thi...
Get the _id of inserted document in Mongo database in NodeJS
...ection.insert that will return the doc or docs inserted, which should have _ids.
Try:
collection.insert(objectToInsert, function(err,docsInserted){
console.log(docsInserted);
});
and check the console to see what I mean.
...
MySQL: What's the difference between float and double?
...00002 | 1.6900000000 |
This is using MySQL 6.7
Query:
SELECT
float_1 + float_2 as 'float add',
double_1 + double_2 as 'double add',
decimal_1 + decimal_2 as 'decimal add',
float_1 * float_2 as 'float multiply',
double_1 * double_2 as 'double multiply',
decimal_1 * decim...
How do you rename a MongoDB database?
... changes to every shard if the DB is sharded, plus the config servers have all the shard metadata in terms of namespaces with their full names.
There would be absolutely no way to do this on a live system.
To do it offline, it would require re-writing every single database file to accommod...
Are table names in MySQL case sensitive?
...
This totally burned me as my code was working great on my local windows environment, but throwing exceptions when moved into production on linux!! Thanks!
– portforwardpodcast
Feb 14 '13 at 21:1...