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What are the best practices for using a GUID as a primary key, specifically regarding performance?
...ve page and index fragmentation and to generally bad performance.
Yes, I know - there's newsequentialid() in SQL Server 2005 and up - but even that is not truly and fully sequential and thus also suffers from the same problems as the GUID - just a bit less prominently so.
Then there's another issu...
“icon-bar” in twitter bootstrap navigation bar
...span tags create three horizontal lines that look like a button, commonly known as the "burger" icon.
Take a look at icon-bar in bootstrap.css:
.navbar-toggle .icon-bar {
display: block;
width: 22px;
height: 2px;
background-color: #cccccc;
border-radius: 1px;
}
It is a block structure,...
What version of Visual Studio is Python on my computer compiled with?
...obscure, lesson 1! Thanks this though Drorhan, it's definitely a "nice to know"!
– dm76
Apr 20 '10 at 16:37
A little l...
What is a “Stub”?
So, carrying on with my new years resolution to get more in to TDD, I am now starting to work more with Rhino Mocks .
6 An...
Relationship between SciPy and NumPy
...ion. Why scipy is preferring the library function over the ufunc, I don't know off the top of my head.
EDIT: In fact, I can answer the log10 question. Looking in the scipy __init__ method I see this:
# Import numpy symbols to scipy name space
import numpy as _num
from numpy import oldnumeric
fro...
What is a “symbol” in Julia?
...t – as data – the foo on the left hand side of this:
foo == "foo"
Now we're getting to the heart of the matter: the difference between a symbol and a string is the difference between foo on the left hand side of that comparison and "foo" on the right hand side. On the left, foo is an identi...
Scala list concatenation, ::: vs ++
...
So is it best practice to avoid ::: in favour of ++ now? Also use +: instead of ::?
– Luigi Plinge
Jul 2 '11 at 23:30
...
Good ways to sort a queryset? - Django
... (487)
Gerald Rudolph (464)
Ulysses Simpson (474)
Harry Truman (471)
And now the combined order_by call:
>>> myauths = Author.objects.order_by('-score', 'last_name')[:5]
>>> for x in myauths: print x
...
James Monroe (487)
Ulysses Simpson (474)
Harry Truman (471)
Benjamin Harri...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
.../y - 1/x^2) but they will be equally complicated.
Let's look at 1/sqrt(y) now. You can try f(x) = x^2 - 1/y, but it will be equally complicated: dx = 2xy / (y*x^2 - 1) for instance.
One non-obvious alternate choice for f(x) is: f(x) = y - 1/x^2
Then: dx = -f/f' = (y - 1/x^2) / (2/x^3) = 1/2 * x * ...
What is the difference between hg forget and hg remove?
...in your working copy. The files are left behind as untracked files and can now optionally be ignored with a pattern in .hgignore.
In other words, I cannot tell if you used hg forget or hg remove when I pull from you. A file that you ran hg forget on will be deleted when I update to that changeset ...