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Non-Relational Database Design [closed]
... single-user applications.
For example, you can usually read a file of 10,000 records AND sort it on a field in less than half a second, an acceptable response time.
Of course, there are reasons to use a database instead of a flat file -- relational operations, data integrity, multiuser capability...
How do I make a list of data frames?
...m(50))
But who does only one simulation? You want to do this 100 times, 1000 times, more! But you don't want 10,000 data frames in your workspace. Use replicate and put them in a list:
sim_list = replicate(n = 10,
expr = {data.frame(x = rnorm(50), y = rnorm(50))},
...
What's the fastest way to merge/join data.frames in R?
...rm(N))
d2 <- data.frame(x=sample(N,N), y2=rnorm(N))
g1 <- sample(1:1000, N, replace = TRUE)
g2<- sample(1:1000, N, replace = TRUE)
d <- data.frame(d1, g1, g2)
library(rbenchmark)
benchmark(replications = 1, order = "elapsed",
merge = merge(d1, d2),
plyr = join(d1, d2),
data.t...
Why are elementwise additions much faster in separate loops than in a combined loop?
...from a page-boundary.
Here's the test code:
int main(){
const int n = 100000;
#ifdef ALLOCATE_SEPERATE
double *a1 = (double*)malloc(n * sizeof(double));
double *b1 = (double*)malloc(n * sizeof(double));
double *c1 = (double*)malloc(n * sizeof(double));
double *d1 = (double*)mall...
Multiple INSERT statements vs. single INSERT with multiple VALUES
I'm running a performance comparison between using 1000 INSERT statements:
4 Answers
4...
What is the significance of ProjectTypeGuids tag in the visual studio project file
...4A-11D0-8D11-00A0C91BC942}
Web Application {349C5851-65DF-11DA-9384-00065B846F21}
Web Site {E24C65DC-7377-472B-9ABA-BC803B73C61A}
WCF {3D9AD99F-2412-4246-B90B-4EAA41C64699}
WPF {60DC8134-EBA5-43B8-BCC9-BB4BC16C2548}
XNA (Windows) {6...
Printing 1 to 1000 without loop or conditionals
Task : Print numbers from 1 to 1000 without using any loop or conditional statements. Don't just write the printf() or cout statement 1000 times.
...
How to parse/format dates with LocalDateTime? (Java 8)
...
@micha what if i have "2016-12-31T07:59:00.000Z" this date formate?
– Dawood Ahmed
Apr 26 '16 at 12:29
15
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Why is processing a sorted array faster than processing an unsorted array?
...I'm thinking of situation of array that looks like: [1,2,3,4,5,...998,999,1000, 3, 10001, 10002] ? will this obscure 3 increase running time? Will it be as long as unsorted array?
– Filip Bartuzi
Nov 9 '14 at 13:37
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Is async HttpClient from .Net 4.5 a bad choice for intensive load applications?
...estion, I recently created some new ones involving much fewer HTTP calls (5000 compared to 1 million previously) but on requests that took much longer to execute (500 milliseconds compared to around 1 millisecond previously). Both tester applications, the synchronously multithreaded one (based on Ht...