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Add a column to existing table and uniquely number them on MS SQL Server
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It would help if you posted what SQL database you're using. For MySQL you probably want auto_increment:
ALTER TABLE tableName ADD id MEDIUMINT NOT NULL AUTO_INCREMENT KEY
Not sure if this applies the values retroactively though. If it doesn't you should just be able to iterate over you...
Scala Doubles, and Precision
...rmat way, but in locales s.a. mine (Finnish), care must be taken to fix to ROOT locale. E.g. "%.2f".formatLocal(java.util.Locale.ROOT,x).toDouble . It seems, format uses ',' because of the locale whereas toDouble is not able to take it in and throws a NumberFormatException. This of course is based o...
Find all packages installed with easy_install/pip?
... print(join(package.location, package._get_metadata("top_level.txt"))) # root directory of this package
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互联网健身的火爆：技术驱动是内因 资本只是点缀 - 资讯 - 清泛网 - 专注C/...
...网健身的创业者们来讲是亟待解决的问题。无论创业者们如何解决这些问题，“业余是细流，专业是大坝”这个基本的原则才是保证整个产品科学发展的关键因素。
改变四：比赛还是要打的，关键是怎么打
对于很多日常的健...
TCP 的那些事儿（下） - 更多技术 - 清泛网 - 专注C/C++及内核技术
...情况太糟糕，反应也很强烈。
sshthresh = cwnd /2
cwnd 重置为 1
进入慢启动过程
2）Fast Retransmit算法，也就是在收到3个duplicate ACK时就开启重传，而不用等到RTO超时。
TCP Tahoe的实现和RTO超时一样。
TCP Reno的...
What's the easy way to auto create non existing dir in ansible
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Right now, this is the only way
- name: Ensures {{project_root}}/conf dir exists
file: path={{project_root}}/conf state=directory
- name: Copy file
template:
src: code.conf.j2
dest: "{{project_root}}/conf/code.conf"
...
How to efficiently build a tree from a flat structure?
...t AssociatedObject { get; set; }
}
IEnumerable<Node> BuildTreeAndGetRoots(List<MyObject> actualObjects)
{
Dictionary<int, Node> lookup = new Dictionary<int, Node>();
actualObjects.ForEach(x => lookup.Add(x.ID, new Node { AssociatedObject = x }));
foreach (var ...
What is the difference between JSON and Object Literal Notation?
...lf. It is derived from a single language.
SQL Language - Hibernate MySQL Dialect, Oracle Dialect,.. which have some changes or added functionality.
Information about the browser and computer of your users.
navigator.appName // "Netscape"
ECMAScript is the scripting language that form...
Select top 10 records for each category
...d
HAVING COUNT(*) <= 10;
update: This example of GROUP BY works in MySQL and SQLite only, because those databases are more permissive than standard SQL regarding GROUP BY. Most SQL implementations require that all columns in the select-list that aren't part of an aggregate expression are al...
How to use Elasticsearch with MongoDB?
...data from everything what is supporting streams (i.e. MongoDB, PostgreSQL, MySQL, JSON files, etc)
Example for MongoDB to Elasticsearch:
Install packages:
npm install elasticbulk
npm install mongoose
npm install bluebird
Create script i.e. script.js:
const elasticbulk = require('elasticbulk')...