Monday, 22 September 2014

Memcached interview questions and answers

Memcached interview questions and answers

What is Memcached?
It is component which stored the data temporary for 1 Hour/ 6 Hour/1 Day etc. When we integrate the Memcached with our application, performance of application increased.
OR
Memcached is open source, high-performance distributed memory object used for caching so that execution can be enhanced at nth level.



How Memcached Works?
  • Try to get to get the detail of user, Browser send the request to application.
  • Application call the Memcached for particular user.
  • If Result found in Memcached, Return the result from Memcached.
  • If Result Not found in Not Memcached, Application send the request to database and save the result in memcached.
  • Each Memcached have one unique key.
  • Get/Set the data works on the behalf of key.
  • you can also delete one or more keys.
  • You can also assign tags to one/more keys.



Who is Author of Memcached?
Danga Interactive


In which Language Memcached is Written?
'C' Language


What is offical website of Nginx?
http://www.memcached.org/


When Memcached's initial version launched?
May 22, 2003




What is the Best Usage of Memcached?
  • Easy to install in windows as well as in unix system.
  • it offers API integration for all the major languages like Java, PHP, C/C++, Python, Ruby, Perl etc
  • Improve the performance of web application by caching
  • Reduce the burden of Db server
  • You can delete one/more values.
  • you can update the values of keys.
  • You can use use "Tags" for keys.



How to install Memcached?
Click Here


Memcached Commands
Connecting to Memcached server with telnet Command?
telnet hostName portNumber


How to get the value of key?
get key


How to set the value of Key?
set key 0 900 4
Format: set [key] [flags] [exptim] [bytes] [noreply]


How to add the value in Key?
add key 0 900 4
Format: add [key] [flags] [exptim] [bytes] [noreply]


How to replace the value of Key?
replace key 0 900 4
Format: replace [key] [flags] [exptim] [bytes] [noreply]


How to append the value of Key?
append key 0 900 4
Format: append [key] [flags] [exptim] [bytes] [noreply]


How to prepend the value of Key?
prepend key 0 900 4
Format: prepend [key] [flags] [exptim] [bytes] [noreply]


How to delete the Key?
delete key 


How to show the Stats?
stats


How to get the Version?
Version


How to close the connection?
quit