2019 nCoV

It's 23th Jan already.2019-nCoV virus is raging in China and some other countries, and also lunar new year tomorrow.Just like 17 years ago, SARS everywhere. Back then I was a senior middle school student. Sat in the classroom every day, the teachers tried sterilization by boiling vinegar in the classroom.Luckily it's spring soon, SARS gone quietly just like how it came. Hundreds of people died, lots of them were doctors and nurses. Feel so sad about them.Then in 2009, there was H1N1. I was at university. I only saw the news on TV and the internet. Weird thing is, in my memory, it was not as bad as in 2003. I was busying getting prepared for job, nothing different. But I just found out today on the internet, about 648 people died in China mainland, while it was 349 in 2003 SARS. Kind of shock news to me.And now, more than 600 people in China mainland got this virus, 17 of them dead. Heard from some news there would be more soon since Wuhan is a big city and many people who work there will go back to their own town to celebrate the lunar new year.In the meantime in the US, CDC says about 6600 died because of the flu.And in Australia, the fire has burnt for months and it's still burning.So many disasters this year. I just wish everything will be OK for everyone and no more disaster to every country and every human being.

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Change Ubuntu 18.04 update source to mirror site in China

## In China, Ubuntu might be slow to updateTo use ubuntu is not a easy thing, and if you are in China, it's even more difficult. Once you want to update your ubuntu. you'd find it's very slow. Because of some well known reason.So it's better to change the update source to some mirror site in China.Here are several famous mirror sites. What you need todo is pick one from below and edit `etc/apt/sources.list`, replace the content in this file.**Better backup you `etc/apt/sources.list` before you do this**### 163 (netease)_source:http://mirrors.163.com/_``` deb http://mirrors.163.com/ubuntu/ bionic main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ bionic-security main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ bionic-updates main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ bionic-proposed main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ bionic-backports main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ bionic main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ bionic-security main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ bionic-updates main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ bionic-proposed main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ bionic-backports main restricted universe multiverse ```### alibaba (aliyun)_source:https://opsx.alibaba.com/mirror_``` deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse ```And here are also two Chinese university mirror, use them only if you are in Chinese university.### tsinghua university``` deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse ```### ustc (university of science and technology of China)``` deb https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse ```Enjoy:)

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Disable Web Search Result in Windows Search 2019

**TL;DR**: download this [windows reg file](https://github.com/HangYang/disable-windows-web-search) and double click to import it. OR- copy the code from below - open you favourite text editor, or just use notepad - paste the code into it - save the file with `.reg` extension - double click the file``` Windows Registry Editor Version 5.00[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Search ] "ConnectedSearchUseWebOverMeteredConnections"=dword:00000000 "AllowCortana"=dword:00000000 "DisableWebSearch "=dword:00000001 "ConnectedSearchUseWeb"=dword:00000000[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Search] "CortanaConsent"=dword:00000000 "BingSearchEnabled"=dword:00000000 "AllowSearchToUseLocation"=dword:00000000 ```Windows is promoting it's `Cortana` and Bing search for a long time. One of the most annoying thing is that it's showing web search content when you search in start menu.So you press `Windows` button, type some keywords, all you want to do is just access your installed app or file quickly, but then you saw some shitty stuff in the result list.Yes, it's showing web search content and even some so called `search suggesttion`. it's based on your keywords and some trends on the web, since you are searching how to disable this, I know that you also think it's totally garbage.In the beginning, Windows gave us an option in the search menu to turn this off. But then Windows known that most of the users hated it, so it just removed this option...I have to use group policy, regeditor to disable it, and have to search for this every time when it updates.To do it step by step is a bit complicated and it's totally a waste of time. So I just create this reg file so that anyone who want to do this can do it by one click.Comment for these reg code in case someone doubt it:---`"ConnectedSearchUseWebOverMeteredConnections"=dword:00000000 ` // \_disable web search use mobile connection`"AllowCortana"=dword:00000000`// disable Cortana`"DisableWebSearch "=dword:00000001` // disable web search`"ConnectedSearchUseWeb"=dword:00000000` // disabled web searech connection`"CortanaConsent"=dword:00000000` // disable Cortana`"BingSearchEnabled"=dword:00000000` // disable bing search in start menu`"AllowSearchToUseLocation"=dword:00000000` // disable search feature access your location---Enjoy :)

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MySQL: Sort Number in String Format

TL;DR: use `key_name` `*` `1`; like``` select id, name, age from users order by salary * 1 ```Well, it's better to store data in a database in a number format. But there is always an accident, sometimes you or your colleague just stored some numbers in the database with string format, of course for some reason.And one day you need to get data from that table and sort the result by that string-number column. Then you find something is not right.If you run a command like this:``` select "1000" > "2" ```you will find that the result is _0_. it means, **100 1**.There are several work around to make this works, like use [conv()](https://dev.mysql.com/doc/refman/8.0/en/mathematical-functions.html#function_conv). So write your SQL like this:``` select * from users order by conv(`salary`, 10, 10) ````conv(original_value, from_base, to_base)` is a MySQL function, to convert a value from one base to another base, as you can also convert a numeric base system 2 to a numeric base system 10.But there is another shorter and cooler way to do this. that's mul the value by 1. Like so:``` select * from users order by salary * 1 ```It works like a charm.Need to notice that if the value is too large, the result will be in _Scientific notation_ like `1e17`.

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