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Update one MySQL table with values from another
I'm trying to update one MySQL table based on information from another.
2 Answers
2
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How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
...ng gemsets:
$ rvm upgrade 1.9.2-p0 1.9.2
Are you sure you wish to upgrade from ruby-1.9.2-p0 to ruby-1.9.2-p136? (Y/n): Y
To replace with the latest stable release of 1.9.2. This avoids clutter.
Some additional helpful tips, thanks to comments (@Mauro, @James, @ACB)
$ rvm list known
# NOTE: yo...
Where is the .NET Framework 4.5 directory?
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Thanks, but what about this page from MSDN. msdn.microsoft.com/en-us/library/bb397428. It mentions a 4.5.0.0 directory?
– Nick Randell
Aug 22 '12 at 9:56
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What is more efficient? Using pow to square or just multiply it with itself?
...second parameter to pow is an int, then the std::pow(double, int) overload from <cmath> will be called instead of ::pow(double, double) from <math.h>.
This test code confirms that behavior:
#include <iostream>
namespace foo
{
double bar(double x, int i)
{
std::c...
Performant Entity Serialization: BSON vs MessagePack (vs JSON)
...SON. That means some type information can be lost when you convert objects from BSON to JSON, but of course only when these special types are in the BSON source. It can be a disadvantage to use both JSON and BSON in single service.
MessagePack is designed to be transparently converted from/to JSON....
Convert floats to ints in Pandas?
I've been working with data imported from a CSV. Pandas changed some columns to float, so now the numbers in these columns get displayed as floating points! However, I need them to be displayed as integers, or, without comma. Is there a way to convert them to integers or not display the comma?
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In Maven 2, how do I know from which dependency comes a transitive dependency?
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To add to @David Crow, here's a dependency:tree example from the Maven site:
mvn dependency:tree -Dincludes=velocity:velocity
might output
[INFO] [dependency:tree]
[INFO] org.apache.maven.plugins:maven-dependency-plugin:maven-plugin:2.0-alpha-5-SNAPSHOT
[INFO] \- org.apache.ma...
PHP Regex to check date is in YYYY-MM-DD format
...nism for this.
The modern solution, with DateTime:
$dt = DateTime::createFromFormat("Y-m-d", $date);
return $dt !== false && !array_sum($dt::getLastErrors());
This validates the input too: $dt !== false ensures that the date can be parsed with the specified format and the array_sum trick...
JavaScript function similar to Python range()
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For a very simple range in ES6:
let range = n => Array.from(Array(n).keys())
From bigOmega's comment, this can be shortened using Spread syntax:
let range = n => [...Array(n).keys()]
share
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How get integer value from a enum in Rails?
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You can get the integer values for an enum from the class the enum is on:
Model.sale_infos # Pluralized version of the enum attribute name
That returns a hash like:
{ "plan_1" => 1, "plan_2" => 2 ... }
You can then use the sale_info value from an instance ...