大约有 47,000 项符合查询结果（耗时：0.0752秒） [XML]
Picking a random element from a set
... the buckets that make up the hashset, which allows us to more efficiently select a random elements. If random elements are necessary in Java, it might be worthwhile to define a custom hash set that allows the user to look under the hood. See [boost's docs][1] for a little more in this. [1] boos...
How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
Set folder browser dialog start location
...
Just set the SelectedPath property before calling ShowDialog.
fdbLocation.SelectedPath = myFolder;
share
|
improve this answer
...
Shell Script — Get all files modified after
...1 | xargs tar --no-recursion -czf myfile.tgz
where find . -mtime -1 will select all the files in (recursively) current directory modified day before. you can use fractions, for example:
find . -mtime -1.5 | xargs tar --no-recursion -czf myfile.tgz
...
Modern way to filter STL container?
...turns the filtered result. eg:
template<typename T>
vector<T> select_T(const vector<T>& inVec, function<bool(const T&)> predicate)
{
vector<T> result;
copy_if(inVec.begin(), inVec.end(), back_inserter(result), predicate);
return result;
}
to use - givin...
Delimiters in MySQL
...TABLE tablea (
col1 INT,
col2 INT
);
INSERT INTO tablea
SELECT * FROM table1;
CREATE TABLE tableb (
col1 INT,
col2 INT
);
INSERT INTO tableb
SELECT * FROM table2;
/* whole procedure ends with the custom delimiter */
END$$
/* Finally, reset the delimiter to...
How to do joins in LINQ on multiple fields in single join
...d2}, (x, y) => x);
While the last argument (x, y) => x is what you select (in the above case we select x).
share
|
improve this answer
|
follow
|
...
Code-first vs Model/Database-first [closed]
...In fact, I still write a lot of stored procedures for the more high volume select statements and such, and then I'll do a function import into the EF model all in the name of performance.
– Steve Wortham
Jun 14 '11 at 14:36
...
JQuery .each() backwards
I'm using JQuery to select some elements on a page and then move them around in the DOM. The problem I'm having is I need to select all the elements in the reverse order that JQuery naturally wants to select them. For example:
...
Changing the status bar text color in splash screen iOS 7
...ng things for getting light color status bar throughout the application.
Select the name of the project in the project navigator.
Select the name of a target from the list in the left column of the project editor.
Click General at the top of the project editor.
Set Status Bar Style -> Light
I...