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Differences between MySQL and SQL Server [closed]
...t the top-n section. In MySQL:
SELECT age
FROM person
ORDER BY age ASC
LIMIT 1 OFFSET 2
In SQL Server (T-SQL):
SELECT TOP 3 WITH TIES *
FROM person
ORDER BY age ASC
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What is the difference between window, screen, and document in Javascript?
...so can be treated as the root of the document object model. You can access it as window
window.screen or just screen is a small information object about physical screen dimensions.
window.document or just document is the main object of the potentially visible (or better yet: rendered) document ob...
Use 'import module' or 'from module import'?
I've tried to find a comprehensive guide on whether it is best to use import module or from module import . I've just started with Python and I'm trying to start off with best practices in mind.
...
Hidden features of Python [closed]
...; x <= 9
True
>>> 5 == x > 4
True
In case you're thinking it's doing 1 < x, which comes out as True, and then comparing True < 10, which is also True, then no, that's really not what happens (see the last example.) It's really translating into 1 < x and x < 10, and x <...
How to find memory leak in a C++ code/project?
...ory only if you've deleted. In the code below, str acquires a new address with the second allocation. The first address is lost irretrievably, and so are the 30 bytes that it pointed to. Now they're impossible to free, and you have a memory leak:
char* str = new char [30]; // Give str a memory addr...
no gravity for scrollview. how to make content inside scrollview as center
...
I had the same issue and finally figured it out. This is for a vertical ScrollView.
Put your ScrollView inside a RelativeLayout and center it in the RelativeLayout. In order for this to work, your ScrollView should have
android:layout_height="wrap_content"
Thi...
Is a view faster than a simple query?
...ueries.
Update: At least three people have voted me down on this one. With all due respect, I think that they are just wrong; Microsoft's own documentation makes it very clear that Views can improve performance.
First, simple views are expanded in place and so do not directly contribute to perf...
Peak detection in a 2D array
...m filter. Here is the result on your first dataset of 4 paws:
I also ran it on the second dataset of 9 paws and it worked as well.
Here is how you do it:
import numpy as np
from scipy.ndimage.filters import maximum_filter
from scipy.ndimage.morphology import generate_binary_structure, binary_ero...
Syntax behind sorted(key=lambda: …)
I don't quite understand the syntax behind the sorted() argument:
9 Answers
9
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Difference between Key, Primary Key, Unique Key and Index in MySQL
...users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have to go through all the records of the table: this is slow, because the more records you have in your database, the more work it has to do to find the result. On the other hand, a...