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PreparedStatement IN clause alternatives?
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An analysis of the various options available, and the pros and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one pre...
How efficient can Meteor be while sharing a huge collection among many clients?
...iption provides; the Mongo driver, which watches the
database for changes; and the merge box, which combines all of a
client's active subscriptions and sends them out over the network to the
client.
Publish functions
Each time a Meteor client subscribes to a collection, the server runs a
publish f...
Rounding up to next power of 2
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This thread is still well referenced but this answer (and most others) are highly outdated. CPUs have an instruction to help this (actually already at that time?). From : jameshfisher.com/2018/03/30/round-up-power-2.html uint64_t next_pow2(uint64_t x) { return x == 1 ? 1 : 1<...
What is the difference between canonical name, simple name and class name in Java Class?
... uniqueness of canonical names within it by clashing fully qualified class and package names at compile time. However JVMs must accept such name clashes, and thus canonical names do not uniquely identifies classes within a ClassLoader. (In hindsight, a better name for this getter would have been get...
What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
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var a = [], // these are the same
b = new Array(), // a and b are arrays with length 0
c = ['foo', 'bar'], // these are the same
d = new Array('foo', 'bar'), // c and d are arrays with 2 strings
// these are different:
e = [3] // e.length =...
How to Correctly Use Lists in R?
...st?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
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Ignore outliers in ggplot2 boxplot
...gplot(df, aes(y = y)) + geom_boxplot(aes(x = factor(1)))
# compute lower and upper whiskers
ylim1 = boxplot.stats(df$y)$stats[c(1, 5)]
# scale y limits based on ylim1
p1 = p0 + coord_cartesian(ylim = ylim1*1.05)
share
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How to generate all permutations of a list?
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Starting with Python 2.6 (and if you're on Python 3) you have a standard-library tool for this: itertools.permutations.
import itertools
list(itertools.permutations([1, 2, 3]))
If you're using an older Python (<2.6) for some reason or are just...
How to validate date with format “mm/dd/yyyy” in JavaScript?
...;
var year = parseInt(parts[2], 10);
// Check the ranges of month and year
if(year < 1000 || year > 3000 || month == 0 || month > 12)
return false;
var monthLength = [ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 ];
// Adjust for leap years
if(year % 400...
Version number comparison in Python
I want to write a cmp -like function which compares two version numbers and returns -1 , 0 , or 1 based on their compared valuses.
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