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Difference between Key, Primary Key, Unique Key and Index in MySQL
...imary key is a column, or a combination of columns, that can uniquely identify a row. It is a special case of unique key. A table can have at most one primary key, but more than one unique key. When you specify a unique key on a column, no two distinct rows in a table can have the same value.
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Play a Sound with Python [duplicate]
...iodev import AFMT_S16_NE
except ImportError:
from sys import byteorder
if byteorder == "little":
AFMT_S16_NE = ossaudiodev.AFMT_S16_LE
else:
AFMT_S16_NE = ossaudiodev.AFMT_S16_BE
dsp.setparameters(AFMT_S16_NE, nc, fr)
data = s.readframes(nf)
s.close()
dsp.write(data)
dsp.close()
(Cre...
Setting the Vim background colors
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How to index characters in a Golang string?
...ters. Strings behave like slices of bytes. A rune is an integer value identifying a Unicode code point. Therefore,
package main
import "fmt"
func main() {
fmt.Println(string("Hello"[1])) // ASCII only
fmt.Println(string([]rune("Hello, 世界")[1])) // UTF-8
fmt.Println(st...
Media Queries: How to target desktop, tablet, and mobile?
...ons thereof, be cognizant of the order of your rules, keeping in mind that if multiple rules match the same element, the later rules will override the earlier rules.
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Rails hidden field undefined method 'merge' error
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How to join components of a path when you are constructing a URL in Python
...eason.
So, I'd use something like '/'.join(s.strip('/') for s in pieces) (if the leading / must also be ignored -- if the leading piece must be special-cased, that's also feasible of course;-).
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How do I clone a specific Git branch? [duplicate]
...ch many people prefer.
You may also want to make sure you understand the difference. And the difference is: by invoking git clone --branch <branchname> url you're fetching all the branches and checking out one. That may, for instance, mean that your repository has a 5kB documentation or wiki ...
How to change the name of the active scheme in Xcode?
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Why should the “PIMPL” idiom be used? [duplicate]
...
It's a pain to maintain though. But then again, if it is a library class the methods should not be changed much anyway. The code I'm looking at seems to be taking the safe road and using pimpl everywhere.
– JeffV
Sep 13 '08 at 15:23
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