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Is there a REAL performance difference between INT and VARCHAR primary keys?
...ring the test.
148.6 GB SSD drive, with plenty of free space.
Ubuntu 16.04 64-bit
MySQL Ver 14.14 Distrib 5.7.20, for Linux (x86_64)
The tables:
create table jan_int (data1 varchar(255), data2 int(10), myindex tinyint(4)) ENGINE=InnoDB;
create table jan_int_index (data1 varchar(255), data2 int(10...
Find the Smallest Integer Not in a List
...st in memory. In the form the question was asked, this would require O(N) 64-bit words.)
@Jorn comments that steps 1 through 3 are a variation on counting sort. In a sense he is right, but the differences are significant:
A counting sort requires an array of (at least) Xmax - Xmin counters wh...
What is the difference between a weak reference and an unowned reference?
...e: String) { self.name = name }
}
class CreditCard {
let number: UInt64
unowned let customer: Customer
init(number: UInt64, customer: Customer) { self.number = number; self.customer = customer }
}
In this example, a Customer may or may not have a CreditCard, but a CreditCard will alwa...
What happens to a declared, uninitialized variable in C? Does it have a value?
... klutt
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answered Oct 20 '09 at 21:27
bdonlanbdonlan
197k2626 gold b...
Is floating-point math consistent in C#? Can it be?
... I found this not easier than using integers directly.
Implement FixedPoint64 in C#. I found this rather hard to do. For some operations intermediate integers of 128bit would be useful. But .net doesn't offer such a type.
Implement a custom 32 bit floatingpoint. The lack of a BitScanReverse intrinsi...
jQuery selectors on custom data attributes using HTML5
...S: test was performed on MacOs High Sierra 10.13.3 on Chrome 67.0.3396.99 (64-bit), Safari 11.0.3 (13604.5.6), Firefox 59.0.2 (64-bit). Below screenshot shows results for fastest browser (Safari):
PureJS was faster than jQuery about 12% on Chrome, 21% on Firefox and 25% on Safari. Interestingly s...
List comprehension rebinds names even after scope of comprehension. Is this right?
...4, 55: 55, 56: 56, 57: 57, 58: 58, 59: 59, 60: 60, 61: 61, 62: 62, 63: 63, 64: 64, 65: 65, 66: 66, 67: 67, 68: 68, 69: 69, 70: 70, 71: 71, 72: 72, 73: 73, 74: 74, 75: 75, 76: 76, 77: 77, 78: 78, 79: 79, 80: 80, 81: 81, 82: 82, 83: 83, 84: 84, 85: 85, 86: 86, 87: 87, 88: 88, 89: 89, 90: 90, 91: 91, 9...
What is a bank conflict? (Doing Cuda/OpenCL programming)
...d with a granuity of 32bit (so byte 0-3 are in bank 1, 4-7 in bank 2, ..., 64-69 in bank 1 and so on). For a better visualization it basically looks like this:
Bank | 1 | 2 | 3 |...
Address | 0 1 2 3 | 4 5 6 7 | 8 9 10 11 |...
Address | 64 65 66 67 | 68 69...
PHP CURL DELETE request
...
BolliBolli
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...
What are the advantages of NumPy over regular Python lists?
...ion cells -- neither approach would fit in a 32-bit architecture, but with 64-bit builds NumPy would get away with 4 GB or so, Python alone would need at least about 12 GB (lots of pointers which double in size) -- a much costlier piece of hardware!
The difference is mostly due to "indirectness" --...