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  Do you really understand Geolocation?

LBS(Location based service) services continue to emerge, it seems that every product has some relationship with maps. But to be honest, do you really understand what is Geolocation? Not necessarily. Although lots of products have LBS service, they can be categorized as sign, search, navigation and information display, these are functional features of the map as a software should have. However, Geolocation is not software, it is just a functional feature, a functional feature of all LBS applicat...

   geolocation,app,significance     2012-10-22 12:11:41

  12 useful Chrome commands

Many useful features of Chrome don't show up on its menus. You can access them through the chrome:// command. In this article we will introduce 12 useful chrome:// commands. 1. chrome://flags It can be used to turn on or turn off some chrome features. 2. chrome://dns This command will show the domain name list caught by the browser. 3. chrome://downloads You can access this through chrome menu as well. The shortcut is Ctrl+J 4. chrome://extensions This command equals to Menu->Tools->Ext...

   Chrome,chrome://     2013-01-25 04:38:03

  Can two new objects point to the same memory address in GoLang?

Do you have any idea what the output will be for below GoLang snippet? package main import ( "fmt" ) type obj struct{} func main() { a := &obj{} fmt.Printf("%p\n", a) c := &obj{} fmt.Printf("%p\n", c) fmt.Println(a == c) } Many people would think that a and c are two different object instances which have different memory addresses. Hence a == c will be false. But if you try to run the above program, you would see below output 0x5781c8 0x5781c8 true To get to know the reason wh...

   GO,GOLANG,VARIABLE ESCAPE,ZEROBASE     2019-04-06 01:19:52

  How expensive is a MySQL query?

Database access speed is always the bottle neck of many applications. Many application have large amount of data to search, retrieve and display nowadays. How do we improve the performance of our applications, how do we reduce the cost of database access? Apart from the design of database, the quality of the query is also one important factor to take care.  But before that, we need to know how much network traffic a query will consume. Yunyang,Zhang from Nubee in Singapore did some research...

   MySQL,Network traffic,Query     2013-04-09 05:13:33

  Reproduce "MySQL server has gone away" in PHP

If you want to debug the issue of "MySQL server has gone away", you can reproduce it with below steps: Modify configuration file: sudo vi /etc/mysql/my.cnf  Make below changes: [mysqld]   wait_timeout = 30   interactive_timeout = 30  Restart the service: sudo /etc/init.d/mysql restart  Write below PHP codes: $link = mysql_connect('127.0.0.1', 'root', 'root');   if (!$link)&nbs...

   MySQL,debug,rMySQL server has gone away     2013-04-15 11:33:14

  Sites to go if you want to learn web development

Before you start to do web development, either for a hobby or for your start up project, you should be prepared for learning many different technologies including both front end and back end. You may need to deal with UI design, business logic design, data store and infrastructure setup etc. This seems a very complex. Indeed, if you know where you should go, the  it's actually not so hard. Here are some sites you should go when you face issues while you are doing web development. These site...

   Web development,Resource,Site     2013-09-19 08:12:23

  Some thoughts about Facebook native app

On Techcrunch Disrupt last month, Facebook CEO Mark Zuckerberg's remarks about their mobile app sparked a denunciation against Web App. HTML 5 seems to have become the bottleneck of poor experience of all related mobile applications. From the user perspective, Facebook native iOS App rates from the 1.5 star to four star now; since the introduction of new native app, the user usage is doubled. It's not easy to have a huge rise of user usage for such a big app like Facebook. Especially consid...

   Facebook, Native app, Analysis     2012-10-12 20:38:11

  What is Deep Web- all you need to know about it?

Deep web is the most nefarious out of sight underground area that exists and not accessible to the public domain. The deep web sites cannot be accessed through standard search engines. Many experts believe to have compared this part of the internet hidden from paywalls and forms. The truth is that deep web is a hidden iceberg while the usual internet available to the public domain is just the tip of the iceberg. That part of what is available from search engines such as Bing or Google ...

   DEEP WEB,DARK WEB     2018-07-05 08:26:58

  SQLite C/C++ function interfaces

Some simple introduction to the SQLite function interfaces. First let's check some error codes defined in SQLite3 (They are in SQLite3.h file in the SQLite installation).#define SQLITE_OK           0   /* Successful result */  /* beginning-of-error-codes */  #define SQLITE_ERROR        1   /* SQL error or missing database */  #define SQLITE_INTERNAL     2&nb...

   SQLite,Function interface,C/C++     2012-07-04 12:23:43

  bash network interface

Some of us may have seen /dev/tcp/<host>/<port> before, is this a special file system implemented in some BSD kernel? Because there is no /dev/tcp in Linux. Actually, this one is implemented in bash. We no need to rely on wget,nc to do network connection. It's very easy to use this interface: bash-4.2$ cat </dev/tcp/time.nist.gov/13 56188 12-09-18 15:34:26 50 0 0 733.5 UTC(NIST) * bash-4.2$ exec 3<>/dev/tcp/www.w3.org/80 bash-4.2$ echo -e "GET / HTTP/1.0\n\n" >&3 b...

   Bash,Network interface,/dev/tcp     2013-07-20 00:57:52

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