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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...erally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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How to perform runtime type checking in Dart?
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is and is! can be found in the Operators section of the Dart language tour.
– Curly
Jun 25 '19 at 16:02
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Fastest way to count exact number of rows in a very large table?
...ECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
25 Answers
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How to Vertical align elements in a div?
I have a div with two images and an h1 . All of them need to be vertically aligned within the div, next to each other.
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What are JavaScript's builtin strings?
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First of all, I would like to thank Jason and all the contributors for playing with that funny snippet. I have written that piece of code just for fun in order to send it to my wife on February 14 :) Having only Chrome installed on the laptop I had no options to chec...
C# Lambda expressions: Why should I use them?
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Lambda expressions are a simpler syntax for anonymous delegates and can be used everywhere an anonymous delegate can be used. However, the opposite is not true; lambda expressions can be converted to expression trees which allows for a lot of the magic like LINQ to SQL.
The following ...
How to find if a given key exists in a C++ std::map
I'm trying to check if a given key is in a map and somewhat can't do it:
14 Answers
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Git diff against a stash
...h show -p stash@{1}
From the git stash manpages:
By default, the command shows the diffstat, but it will accept any
format known to git diff (e.g., git stash show -p stash@{1} to view
the second most recent stash in patch form).
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How can I extend typed Arrays in Swift?
... answered Nov 6 '15 at 0:52
Andrew SchreiberAndrew Schreiber
11.2k66 gold badges3737 silver badges5151 bronze badges
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How to sort an array of objects by multiple fields?
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Update: Here is an "optimized" version. It does a lot more preprocessing and creates a comparison function for each sorting option beforehand. It might need more more memory (as it stores a function for each sorting option, but it should preform a bit better as it does not have to determine the co...