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MongoDB Many-to-Many Association
...ey use their own N1QL. This is an example of a JOIN from their tutorials:
SELECT usr.personal_details, orders
FROM users_with_orders usr
USE KEYS "Elinor_33313792"
JOIN orders_with_users orders
ON KEYS ARRAY s.order_id FOR s IN usr.shipped...
In which case do you use the JPA @JoinTable annotation?
... UPDATE There aren't duplicates entries in my database, the hibernate is selecting with the left outer join and I dont know why..
– MaikoID
Dec 12 '12 at 20:49
2
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What is a Portable Class Library?
...g screenshots and detailed matrices showing available features across your selections if you're into that sort of thing.
See Portable Library Tools anouncement blog post, which starts:-
The Portable Library Tools CTP adds a new "Portable Class Library" project template to Visual Studio that c...
Simple explanation of MapReduce?
...e reduced to a scalar value.
So if you think of it like a SQL statement
SELECT SUM(salary)
FROM employees
WHERE salary > 1000
GROUP by deptname
We can use map to get our subset of employees with salary > 1000
which map emits to the barrier into group size buckets.
Reduce will sum each of...
What is the dependency inversion principle and why is it important?
...l never be able to deploy his application without the logging library John selected. If John follows the DIP, however, Sam is free to provide an adapter and use whatever logging library he chooses. The DIP isn't about convenience, but coupling.
– Derek Greer
...
How does the const constructor actually work?
...ting-widgets-b7ac56dbbeb1 "Use const to build your widgets Without const, selective rebuilding of the sub-tree does not happen. Flutter creates a new instance of each widget in the sub-tree and calls build() wasting precious cycles especially if your build methods are heavy."
–...
Why doesn't Dijkstra's algorithm work for negative weight edges?
... the "closed" nodes is indeed minimal, and thus the node that will next be selected is also minimal.
The idea of it is: If we have a vertex in open such that its cost is minimal - by adding any positive number to any vertex - the minimality will never change.
Without the constraint on positive numb...
Break a previous commit into multiple commits
...g git reset HEAD~, go through the patches individually using git add -p to select the ones you want in each commit
Edit the working copy to remove the changes you do not want; commit that interim state; and then pull back the full commit for the next round.
Option 2 is useful if you're splitting a...
What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
...ow demonstrate the noticeable artifacting of lossy compression algorithms; select the thumbnail image to view the full size version.
Each format is different as described below:
JPEG
JPEG (Joint Photographic Experts Group) files are (in most cases) a lossy format; the DOS filename extension is JPG...
How to implement a rule engine?
..."Contains", "C#" )
};
// compile the rules once
var compiledRules = rules.Select(r => CompileRule(r)).ToList();
public bool MatchesAllRules(User user)
{
return compiledRules.All(rule => rule(user));
}
Here is the implementation of BuildExpr:
Expression BuildExpr(Rule r, ParameterExpress...