![How do giant sites like Facebook and Google check Username or Domain availability so fast? - HackerEarth Blog How do giant sites like Facebook and Google check Username or Domain availability so fast? - HackerEarth Blog](https://blog-c7ff.kxcdn.com/blog/wp-content/uploads/2017/03/blog_1-02_Tinified.jpg)
How do giant sites like Facebook and Google check Username or Domain availability so fast? - HackerEarth Blog
![itunes - How to access apple support forum on "This username ... is already taken, please choose another. Another has been provided" message? - Ask Different itunes - How to access apple support forum on "This username ... is already taken, please choose another. Another has been provided" message? - Ask Different](https://i.stack.imgur.com/naMDa.png)
itunes - How to access apple support forum on "This username ... is already taken, please choose another. Another has been provided" message? - Ask Different
![That Username Is Taken. Try Another. Gmail | That Username Is Taken. Try Another Meaning In Hindi - YouTube That Username Is Taken. Try Another. Gmail | That Username Is Taken. Try Another Meaning In Hindi - YouTube](https://i.ytimg.com/vi/kyDVDGYfabk/maxresdefault.jpg)