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SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...
Mongoose, Select a specific field with find
... I think .select just is a filter to choose field after you get all of that, my recommendation is to use .find({}, 'name -_id')
– hong4rc
Mar 2 '19 at 16:15
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What is the difference between ManualResetEvent and AutoResetEvent in .NET?
...or. The ManualResetEvent is the door, which needs to be closed (reset) manually. The AutoResetEvent is a tollbooth, allowing one car to go by and automatically closing before the next one can get through.
share
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Python multiprocessing PicklingError: Can't pickle
...the one you posted:
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__args, **self.__kwargs)
File "/usr/lib/p...
What's the meaning of exception code “EXC_I386_GPFLT”?
...hich is the x86's way to tell you that "you did something that you are not allowed to do". It typically DOESN'T mean that you access out of memory bounds, but it could be that your code is going out of bounds and causing bad code/data to be used in a way that makes for an protection violation of som...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
How to apply bindValue method in LIMIT clause?
...
@Ross I cannot specifically answer this- but I can point out that LIMIT and OFFSET are features that were glued on AFTER all this PHP/MYSQL/PDO madness hit the dev circuit... In fact, I believe it was Lerdorf himself who oversaw LIMIT implementatio...
Mock vs MagicMock
My understanding is that MagicMock is a superset of Mock that automatically does "magic methods" thus seamlessly providing support for lists, iterations and so on... Then what is the reason for plain Mock existing? Isn't that just a stripped down version of MagicMock that can be practically ...
How does Trello access the user's clipboard?
...source code Trello uses to accomplish the clipboard trick.
We don't actually "access the user's clipboard", instead we help the user out a bit by selecting something useful when they press Ctrl+C.
Sounds like you've figured it out; we take advantage of the fact that when you want to hit Ctrl+C, ...
In a Django form, how do I make a field readonly (or disabled) so that it cannot be edited?
...hanged his example to work with Django 1.3, using get_readonly_fields.
Usually you should declare something like this in app/admin.py:
class ItemAdmin(admin.ModelAdmin):
...
readonly_fields = ('url',)
I've adapted in this way:
# In the admin.py file
class ItemAdmin(admin.ModelAdmin):
...
