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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 }
...
Can I access constants in settings.py from templates in Django?
...neric views, and many of the core and contrib apps, additional context is called extra_context, and very often it is included in the view's arguments.
– Soviut
Jun 1 '09 at 1:33
...
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 =...
Do I set properties to nil in dealloc when using ARC?
...
Short answer: no, you do not have to nil out properties in dealloc under ARC.
Long answer: You should never nil out properties in dealloc, even in manual memory management.
In MRR, you should release your ivars. Nilling out properties means calling setters, which may invoke code that...
Make a link open a new window (not tab) [duplicate]
... @JeanGkol I rewrote my answer to clarify the issue. Technically, it is working, because it opens a new browsing context (like it is supposed to do). The problem is, that in modern browsers "browsing context" is a tab instead of a window (you can change this in the settings though).
...
Private properties in JavaScript ES6 classes
...class fields work. You can't currently use this in constructor before you call super(). Yet babel puts them before super.
– seeker_of_bacon
Oct 3 '18 at 16:23
...
Behaviour of increment and decrement operators in Python
...e applied on a variable (like ++count ). It compiles, but it does not actually change the value of the variable!
9 Answers...
List of special characters for SQL LIKE clause
What is the complete list of all special characters for a SQL (I'm interested in SQL Server but other's would be good too) LIKE clause?
...
How do I set a variable to the output of a command in Bash?
... be done with $(command) or "$(command)", which I find easier to read, and allows for nesting.
OUTPUT=$(ls -1)
echo "${OUTPUT}"
MULTILINE=$(ls \
-1)
echo "${MULTILINE}"
Quoting (") does matter to preserve multi-line variable values; it is optional on the right-hand side of an assignment, as w...
How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...