大约有 44,000 项符合查询结果（耗时：0.0606秒） [XML]
How to 'bulk update' with Django?
...
Update:
Django 2.2 version now has a bulk_update.
Old answer:
Refer to the following django documentation section
Updating multiple objects at once
In short you should be able to use:
ModelClass.objects.filter(name='bar').update(name="foo")
...
How to pass a class type as a function parameter
...class of the instances of returningClass
handler(returningClass())
}
Now there's the problem of constructing an instance of T to pass to handler: if you try and run the code right now the compiler will complain that T is not constructible with (). And rightfully so: T has to be explicitly cons...
Convert NSArray to NSString in Objective-C
...rWords = [myString componentsSeparatedByString:@" "];
// yourWords is now: [@"This", @"is", @"a", @"test", @"string"]
if you need to split on a set of several different characters, use NSString’s componentsSeparatedByCharactersInSet:
NSString *yourString = @"Foo-bar/iOS-Blog";
NSArray *you...
What is the difference between “def” and “val” to define a function
...ng var as I need to change it to 3 later
val sq = x*x // evaluates right now
x = 3 // no effect! sq is already evaluated
println(sq)
Surprisingly, this will print 4 and not 9! val (even var) is evaluated immediately and assigned.
Now change val to def.. it will print 9! Def is a function cal...
Run cURL commands from Windows console
...ble, but rather just need to e.g. see or save the results of a GET request now and again, can use powershell directly. From a normal command prompt, type:
powershell -Command "(new-object net.webclient).DownloadString('http://example.com')"
which, while a bit wordy, is similar to typing
curl htt...
Meaning of Choreographer messages in Logcat [duplicate]
...nstalled the latest versions of SDK (API 16) and got the latest ADT. I'm now seeing these messages in the logcat, that I'm quite sure, I haven't seen before. Does anyone have an idea about this?
...
node.js remove file
...s.exists. Because according to the latest node.js documentation, fs.exists now deprecated.
For example:-
fs.stat('./server/upload/my.csv', function (err, stats) {
console.log(stats);//here we got all information of file in stats variable
if (err) {
return console.error(err);
}
...
What is a difference between
... arrays are what we call reifiable types. This means that at runtime Java knows that this array was actually instantiated as an array of integers which simply happens to be accessed through a reference of type Number[].
So, as you can see, one thing is the actual type of the object, and another thin...
Download file from an ASP.NET Web API method using AngularJS
...e available saveBlob support caused an exception; hence why the code below now tests for navigator.msSaveBlob separately. Thanks? Microsoft
// Based on an implementation here: web.student.tuwien.ac.at/~e0427417/jsdownload.html
$scope.downloadFile = function(httpPath) {
// Use an arraybuffer
...
git: Switch branch and ignore any changes without committing
...bsentmindedly made minor changes to the code that are not worth keeping. I now want to change branches, but git gives me,
1...