大约有 40,000 项符合查询结果（耗时：0.0665秒） [XML]
How do you make a web application in Clojure? [closed]
... I worked on Java projects, but not Java-the-world. I never made a web app from scratch in Java. If I have to do it with Python, Ruby, I know where to go (Django or Rails), but if I want to make a web application in Clojure, not because I'm forced to live in a Java world, but because I like the lang...
How to return an empty ActiveRecord relation?
...ils 4
In Rails 4, a chainable ActiveRecord::NullRelation will be returned from calls like Post.none.
Neither it, nor chained methods, will generate queries to the database.
According to the comments:
The returned ActiveRecord::NullRelation inherits from
Relation and implements the Null Obje...
Why Collections.sort uses merge sort instead of quicksort?
...
Highly likely from Josh Bloch §:
I did write these methods, so I suppose I'm qualified to answer. It is
true that there is no single best sorting algorithm. QuickSort has
two major deficiencies when compared to mergesort:
...
Can scripts be inserted with innerHTML?
...ng something like innerHTML? Is there a way to do this with document.write from within a function?
– Craig
Jul 29 '09 at 1:23
5
...
C compile error: “Variable-sized object may not be initialized”
...ot know how many elements there are in the array (I am also assuming here, from the compiler error that length is not a compile time constant).
You must manually initialize that array:
int boardAux[length][length];
memset( boardAux, 0, length*length*sizeof(int) );
...
Rails “validates_uniqueness_of” Case Sensitivity
...t for the new record and fail with a ugly server exception that comes back from the SQL adapter. If you do not have a database constraint, the insert will succeed and you now have two rows with 'foo' as the name.
See also "Concurrency and integrity" in the validates_uniqueness_of Rails documentat...
Difference between Document-based and Key/Value-based databases?
...-value stores like redit doesn't allow you to store nested key:values? And from your description, then storing a whole database (from RDBMS) into Cassandra doesn't sound very clever cause it doesn't allow flexible query and has limited nesting depth, am I right?
– never_had_a_n...
What does static_assert do, and what would you use it for?
... your comment: yes, you can have static_assert just sitting out wherever, from the look of it:
class Foo
{
public:
static const int bar = 3;
};
static_assert(Foo::bar > 4, "Foo::bar is too small :(");
int main()
{
return Foo::bar;
}
$ g++ --std=c++0x a.cpp
a.cpp:7: error:...
Can pandas automatically recognize dates?
Today I was positively surprised by the fact that while reading data from a data file (for example) pandas is able to recognize types of values:
...
REST, HTTP DELETE and parameters
...hods in an environment where PUT/DELETE methods are not available. Judging from your use of the DELETE method, this is not the case.
HTTP error code 409/Conflict should be used for situations where there is a conflict which prevents the RESTful service to perform the operation, but there is still a...