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Difference between clustered and nonclustered index [duplicate]
... every row in your table. This can be anything, really - an INT, a GUID, a string - pick what makes most sense for your scenario.
2) the clustering key (the column or columns that define the "clustered index" on the table) - this is a physical storage-related thing, and here, a small, stable, ever-...
What's the difference between a single precision and double precision floating point operation?
...s 32 bits, its double-precision counterpart will be 64 bits long.
The extra bits increase not only the precision but also the range of magnitudes that can be represented.
The exact amount by which the precision and range of magnitudes are increased depends on what format the program is using ...
Reference — What does this symbol mean in PHP?
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@AcidShout $a - $b works for numbers, but not strings, objects, or arrays.
– mcrumley
Sep 25 '15 at 18:29
49
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What is the purpose of backbone.js?
... and are generally bad form. Data attributes stored in the DOM can only be strings, you will have to parse them in and out again. It's difficult to store things like arrays, dates or objects, and to parse your data in a structured form.
Data attributes look like this:
<p data-username="derek" d...
Use RSA private key to generate public key?
...d mykey.pem file.
openssl rsa -in mykey.pem -pubout > mykey.pub
will extract the public key and print that out. Here is a link to a page that describes this better.
EDIT: Check the examples section here. To just output the public part of a private key:
openssl rsa -in key.pem -pubout -out p...
Why are quaternions used for rotations?
... because they can do more than rotations. But in the case of rotations the extra components are determined in terms of the others.
– JMP
Jan 18 '12 at 23:45
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What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?
...Array, NSDictionary, and NSNumber (just like one can create literals for NSString)
NSArray Literals
Previously:
array = [NSArray arrayWithObjects:a, b, c, nil];
Now:
array = @[ a, b, c ];
NSDictionary Literals
Previously:
dict = [NSDictionary dictionaryWithObjects:@[o1, o2, o3]
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Viewing all defined variables [duplicate]
...s was not obvious in your example because all the variables happened to be strings anyway; however, what it's returning is the type of the name of the variable instead of the type of the variable. To fix this: instead of print type(name) use print eval('type(' + name + ')'). I apologize for posting...
How to achieve function overloading in C?
...ce, and you need to mess about a bit if you want your overloads to support string literals. Still overall pretty cool though.
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How do MySQL indexes work?
...lision number is high cause you'll only perform the second comparison (the string one) against the repeated hashes.
Unfortunately, using this technique, you still need to hit the table to compare the url field.
Wrap up
Some facts that you may consider every time you want to talk about optimizatio...