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What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
...
+100
I created a test suite, precisely to explore these issues (and more) (archived copy).
And in that sense, you can see the performance...
OceanBase使用libeasy原理源码分析：服务器端 - 数据库(内核) - 清泛网 - ...
...y基于libev，对libev不了解的参见 这
这篇主要分析OceanBase 0.4的mergeserver使用libeasy作为服务器端的模式，客户端自然就是MySQL客户端。OceanBase仅仅使用了libeasy的IO线程部分，工作线程是使用了我们自己的线程池。
主要说如下几个...
Remote Connections Mysql Ubuntu
...ss
bind-address = xxx.xxx.xxx.xxx
Or add a
bind-address = 0.0.0.0 if you don't want to specify the IP
Then stop and restart MySQL with the new my.cnf entry. Once running go to the terminal and enter the following command.
lsof -i -P | grep :3306
That should come back something l...
How can I ensure that a division of integers is always rounded up?
...
670
UPDATE: This question was the subject of my blog in January 2013. Thanks for the great question!...
COUNT DISTINCT with CONDITIONS
...count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex, is actually the same as the first one, except that you use case...when clause. In ...
Add a new element to an array without specifying the index in Bash
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|
edited Dec 23 '09 at 9:18
answered Dec 23 '09 at 9:02
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Bash, no-arguments warning, and case decisions
...
if [[ $# -eq 0 ]] ; then
echo 'some message'
exit 0
fi
case "$1" in
1) echo 'you gave 1' ;;
*) echo 'you gave something else' ;;
esac
The Advanced Bash-Scripting Guide is pretty good. In spite of its name, it does treat...
GraphViz - How to connect subgraphs?
...ue statement is required.
digraph G {
compound=true;
subgraph cluster0 {
a -> b;
a -> c;
b -> d;
c -> d;
}
subgraph cluster1 {
e -> g;
e -> f;
}
b -> f [lhead=cluster1];
d -> e;
c -> g [ltail=cluster0,lhead=cluster1];
c -> e [...
Get local IP address in node.js
... net of nets[name]) {
// skip over non-ipv4 and internal (i.e. 127.0.0.1) addresses
if (net.family === 'IPv4' && !net.internal) {
if (!results[name]) {
results[name] = [];
}
results[name].push(net.address);
}
}
...
Random alpha-numeric string in JavaScript? [duplicate]
...ring(length, chars) {
var result = '';
for (var i = length; i > 0; --i) result += chars[Math.floor(Math.random() * chars.length)];
return result;
}
var rString = randomString(32, '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ');
Here's a jsfiddle to demonstrate: htt...