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How do I partially update an object in MongoDB so the new object will overlay / merge with the exist
...n would be that you are happy with $set, but do not want to explicitly set all fields. How would you pass in the data then?
You know you can do the following:
db.collection.update( { _id:...} , { $set: someObjectWithNewData }
...
Installing Java 7 on Ubuntu
to install java I have always used the classic way from the terminal.
I would like to install java manually.
I placed the folder of the JDK on the desk and I set environment variables (PATH, CLASSPATH and JAVA_HOME).
From the terminal, if I type java -version I get printed
...
Read file from line 2 or skip header row
... This is fine UNTIL the file is too large to read. This is fine for small files.
– CppLearner
Feb 5 '18 at 2:05
1
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Dynamically adding a form to a Django formset with Ajax
I want to automatically add new forms to a Django formset using Ajax, so that when the user clicks an "add" button it runs JavaScript that adds a new form (which is part of the formset) to the page.
...
Does Dart support enumerations?
...ase Fruit.apple:
print('it is an apple');
break;
}
// get all the values of the enums
for (List<Fruit> value in Fruit.values) {
print(value);
}
// get the second value
print(Fruit.values[1]);
}
The old approach before 1.8:
class Fruit {
static const APPLE =...
I want to get the type of a variable at runtime
...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here.
Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple:
val x = 5
x.ge...
Rails :include vs. :joins
...de functionality was changed with Rails 2.1. Rails used to do the join in all cases, but for performance reasons it was changed to use multiple queries in some circumstances. This blog post by Fabio Akita has some good information on the change (see the section entitled "Optimized Eager Loading")....
jQuery Validate Plugin - Trigger validation of single field
I've got a form that can optionally be pre-populated via facebook connect. Once a user connects, their name and email are automatically filled in. The problem is that this doesn't trigger the remote validation to check if the email already exists.
...
Django 1.7 - makemigrations not detecting changes
... may happen due to the following reasons:
You did not add the app in INSTALLED_APPS list in settings.py
(You have to add either the app name or the dotted path to the subclass of AppConfig in apps.py in the app folder, depending on the version of django you are using). Refer documentation: INST...
How to read and write INI file with Python3?
...
The standard ConfigParser normally requires access via config['section_name']['key'], which is no fun. A little modification can deliver attribute access:
class AttrDict(dict):
def __init__(self, *args, **kwargs):
super(AttrDict, self).__init...